Chapter 72: Arithmetic

Chapter 72: Arithmetic

Zhu Jingcheng wondered if he had misheard, his mind racing with possibilities.

"Then, you... what do you mean?"

Su Xinbai bit his lip, his mind swirling with Qiu Huanian's words.

What if... he was wrong?

But how could that be? The thought seemed almost too good to be true. Even if Zhu Jingcheng wasn't angry with him anymore, Su Xinbai couldn't bring himself to ask...

Su Xinbai leaned away slightly, his tone polite but firm, "It's late, and I'm tired. Eldest Young Master, you should return to your room and rest."

Zhu Jingcheng responded with a somewhat dejected "Hmm," his shoulders slumping as he turned to leave.

Only then did Su Xinbai notice a large stain on the hem of Zhu Jingcheng's robe, which hadn't been changed or cleaned. His hair was also slightly disheveled, unlike his usual neat appearance.

"What happened to your clothes?"

Zhu Jingcheng quickly hid the stained hem behind him, explaining, "Today, Imperial Envoy Zhao Tianyu summoned the merchants of Xiangping Prefecture to the military camp outside the city. I just returned and haven't had time to change. I must have upset you."

Su Xinbai's brows furrowed, a sense of displeasure and concern rising in his heart.

The shape of the stain suggested it was from mud splashed by a galloping horse, likely because he had been standing too close. Why would the Imperial Envoy summon merchants to the military camp, allowing such a display of power without even giving them time to change clothes? What could be the purpose?

Seeing the look of resignation on Zhu Jingcheng's face, Su Xinbai felt an inexplicable irritation bubbling up inside him.

"Madam, is something wrong?"

"You..." Su Xinbai paused, then added, "Be careful. If you encounter any difficulties, you can seek help from my father."

"After all, he's the one who chose this son-in-law," Su Xinbai muttered under his breath.

Under the candlelight, a look of pleasant surprise gradually spread across Zhu Jingcheng's face. "Madam, are you concerned about me?"

"..."

Su Xinbai placed the brush back on its stand with a slightly louder than usual clink, his frustration evident.

He stood up, stepping around Zhu Jingcheng, and quickly retreated to the inner chamber. The soft silk curtain on the floor obscured his figure, making it impossible to see him.

The servants remained silent, and Zhu Jingcheng stood still for a long moment, a warm, tender feeling rising in his heart.

It seemed that Xinbai didn't dislike him as much as he used to.

He turned his gaze back to the desk, reading through the preliminary plan for the new bookstore and noting a few key points. He decided to clear some time tomorrow to tidy up in advance, lest some clueless family members dampen Su Xinbai's enthusiasm.

Zhu Jingcheng walked to the entrance of the inner chamber and spoke through the curtain, "I'll rest in the study. Sweet dreams, Madam."

After a few seconds, Su Xinbai responded with a "Hmm," his voice still cold but with a lighter tone at the end.

Zhu Jingcheng gathered his courage and asked, "In the future, if Madam receives any books you like, could you let me see them first?"

"...If you want to read them, just come and take them."

Zhu Jingcheng returned to the study with a smile, where his personal servant, Shijuan, awaited, looking puzzled.

"The young master seems to have been charmed. He had a rough day, yet now he's actually smiling."

Zhu Jingcheng's smile didn't fade as he sighed, "Since ancient times, merchants, though amassing great wealth, have always been at the bottom of the social hierarchy. Not kings, not nobles, their silks and satins, gold and jewels turn to ash in an instant, and their generations cannot rise. They are merely tools and facades for officials to exploit the people."

"Now, some within this facade are being used to transport supplies to foreign tribes, aiding the enemy and inciting the court's wrath, causing great anger from the imperial authority. The imperial envoy cannot touch the mastermind, so isn't it natural to take it out on the pawns?"

"Once you see these things clearly, you can bear them."

Zhu Jingcheng took off his dirty coat, shook it, and tossed it onto the rosewood clothes rack. He rolled up his sleeves and walked to the desk.

"But someone cares for me, especially him, so of course, I'm happy."

Zhu Jingcheng spread out the cut paper, pondered over the day's events, and then picked up a brush to write a letter. After sealing it, he handed it to Shijuan.

"Please make another trip and deliver this letter to Du Yunse at Qingfeng Academy. Remember to stay out of sight."

"Young master, rest assured. I've done this several times already, I know the ropes."

...

After the spring outing, Qiu Huanian started getting busy with preparing for Jiu Jiu and Chun Sheng's schooling.

The two children had previously been educated at home, and this was their first time going to an outside school. As a parent, Qiu Huanian couldn't help but worry.

He worried that Jiu Jiu wouldn't get along well with the young ladies and gentlemen from the Zhu family relatives, fearing she might be snubbed due to her rural background.

He worried that Chun Sheng wouldn't adapt to the strict rules of the private school teacher and might rebel again.

Jiu Jiu and Chun Sheng, however, were very excited. Just the thought of going to a new place made everything exciting.

Seeing them like this, Qiu Huanian's mind gradually eased.

He sat in the study, checking the list of school supplies for the two children. Cream Frost pushed open the sliding door with her paw and hopped in gracefully, the small gold lock on her neck swaying.

Qiu Huanian bent down to pick her up and weighed her.

"Have you put on some weight, huh, little one?"

"Meow~" Cream Frost yawned and meowed in a soft, kittenish voice.

The two children who followed closed the door behind them.

"Brother Hua, Cream Frost has gotten bigger," Jiu Jiu said with a smile.

The kitten grew quickly. In less than a month, the cat that Qiu Huanian could easily hold with one hand now needed both hands to carry.

Lion cats are naturally medium to large in size, and Cream Frost, well-fed and well-rested, shot up in size. Her long white fur looked like a fluffy snowball.

Qiu Huanian placed Cream Frost on his lap and played with the small gold lock on her neck.

"You really are a wealthy little lady. Just a few months old and already catching the eye of a rich guy, wearing a pure gold lock."

Cream Frost comfortably lifted her chin, squinted her eyes, and meowed, making Qiu Huanian laugh.

Su Xinbai really clicked with Cream Frost, and Cream Frost was fond of him too. Every time Su Xinbai visited, she would drop her usual cool demeanor and clearly aim to fawn over him. In such a short time, Su Xinbai had specially made a small gold lock with Cream Frost's name engraved on it for her to wear.

When it came to giving gifts to people, Qiu Huanian could still refuse, but when it came to the cat, he really had no choice but to let the rich guy do as he pleased.

Qiu Huanian scratched Cream Frost's pleasantly textured chin while showing the list to Jiu Jiu and Chun Sheng.

"Each of you will have a book box, a set of brushes, ink, and an inkstone, a paperweight, a soft cushion, and a drinking cup. These items are the same for both of you. If we already have them at home, we won't buy new ones."

Qiu Huanian said to Jiu Jiu, "Xinbai said he would give you the same items as Zhu Xian. You can see which ones you can exchange later."

Jiu Jiu had already made up her mind, "Brother Hua, I don't need anything from the Zhu family since we already have things prepared at home."

"I'm just worried that if your things are too plain, you might be looked down upon by the Zhu family."

Qiu Huanian had never attended an ancient academy and wasn't sure how common things like school violence or bullying were. But thinking about Du Yunjing, who was so jealous of Du Yunse that it twisted him, he knew that conflicts were inevitable at school.

Jiu Jiu said, "I'm going there to study. As long as I'm neatly dressed and work hard, that's all that matters. If anyone laughs at me for that, it's their fault, not mine."

Qiu Huanian patted Jiu Jiu's head. Over the past year, Jiu Jiu had grown ten centimeters taller, and Qiu Huanian now had to raise his elbow a bit to reach her head.

"I'm really happy you see it that way."

Qiu Huanian then instructed Chun Sheng, "At the private academy, you must respect the teacher. Don't get distracted during class, and don't play around or shout with your classmates, understand?"

"Brother Hua, don't worry, my sister has already told me many times!"

Qiu Huanian tapped his nose, "Then I'll be keeping an eye on how you do."

Since they would need to take the kids to and from school every day, Qiu Huanian decided to make the most of the family carriage and hire a driver.

Having been in the city for some time now, apart from a brief meeting when they first arrived, Qiu Huanian hadn't had a proper catch-up with the Shu family couple and the Huang sisters. Taking advantage of the good weather, Qiu Huanian decided to catch up with friends and Meng Yuanling and also inquire about hiring a suitable driver.

When they arrived near the Gongyuan where Shuyi Inn was located, the Huang sisters' newly opened Xianwei House was also on these streets. It was still before lunch, and the two-story restaurant wasn't very busy. Huang Erniang was in the main hall greeting customers, while Huang Daniang was behind the counter keeping the books.

Seeing Qiu Huanian, Huang Erniang's eyes lit up. She draped a white cloth over her shoulder and hurried out to greet him.

"Brother Hua, why didn't you let us know you were coming? We didn't prepare properly."

"I just felt like coming, I can't trouble you to prepare every time." Qiu Huanian introduced Meng Yuanling, "This is my friend, also the husband of our family's younger brother, a young lad from Qingfu Town, named Meng Yuanling."

Meng Yuanling wasn't shy at all and greeted Huang Erniang and Huang Daniang with a smile. Since they were all from Zhang County, they quickly became familiar.

"It feels like everyone around Brother Hua is exceptionally good-looking. We sisters are also benefiting from it."

"You sisters are healthy, hardworking, and capable, of course, you're good-looking."

"Hahaha, Brother Hua, you're so well-read and eloquent. Next time some drunkard calls me rough-handed, I'll use your words to retort."

The sisters led Qiu Huanian and Meng Yuanling into the restaurant. Huang Daniang gave a few instructions to the waiter and invited them to a private room upstairs for a chat.

"Last time we didn't get to ask in detail, how is your restaurant doing?"

"It's harder to establish ourselves in the city than in the county, but once we stabilize, the earnings are also higher. Thanks to the reputation of being the top in the Hundred Tastes Competition, we've already made a name for ourselves in the past few months. The young master of the Zhu family often brings people to dine here, which has attracted many customers."

Huang Daniang's successful return to the city with her sister was largely due to Qiu Huanian and Du Yunse. She didn't hold back, "Now the restaurant's monthly income is over fifty taels of silver. After covering rent and ingredient costs, we net about twenty taels."

The business was quite prosperous, but the Huang sisters, being women managing such a large enterprise, undoubtedly faced many difficulties and grievances.

Huang Daniang enthusiastically said, "I'll go invite Sister Yi and the others. You hang tight, I'll cook up a feast for lunch, and we'll have a great time."

The ingredients at the restaurant were all pre-washed and prepared. In less than half an hour, Huang Daniang brought out a table full of delicious dishes. Zheng Yiwan and Shu Huacai also brought Ru Tang along.

At around ten years old, girls are in a growth spurt. After not seeing her for half a year, Ru Tang had blossomed into a graceful young lady, her figure taller, wearing a silver-red coat and a green skirt with gold trim, her dark hair adorned with a few peach blossom buds.

Zheng Yiwan said they had hired a tutor for Ru Tang, teaching her the basics of reading, writing, accounting, and sewing.

Compared to poetry and literature, Ru Tang was more interested in math. She begged her parents to buy her a widely circulated math book from the Yu Dynasty called *The Classic of Mathematics*. Unfortunately, she found it difficult to understand and felt quite frustrated.

Hearing Ru Tang’s words, Qiu Huanian felt inspired and started forming some ideas.

Upon learning that Su Xinbai planned to establish a publishing house for practical manuscripts, Qiu Huanian also wanted to write some books. It would not only help supplement the family income but also leave his mark on the world.

Agricultural books impact the livelihoods of countless farmers. Without reliable data, Qiu Huanian didn’t dare write carelessly. Completing an agricultural book would take a long time. As for other types of books, Qiu Huanian hadn’t yet decided what to write.

In his past life, he was a science major. After becoming a self-media blogger, he developed his skills in brainstorming and writing content. However, writing the elegant, classical prose revered in ancient times was still too difficult for him.

After hearing Ru Tang talk about her struggles with math, Qiu Huanian found the perfect niche. What could be more practical and fitting for him to write than simple, easy-to-understand beginner math books?

In ancient times, when classical texts were highly revered, scholars’ math skills were generally poor. Many struggled with basic two-digit addition and subtraction without an abacus. After a year of Qiu Huanian’s occasional tutoring, Jiu Jiu and Chun Sheng’s math skills had already surpassed their peers.

If there were suitable beginner math books, they could not only improve the public’s math skills but also make it easier for those genuinely interested in math to get started. With a solid foundation in the basics, tackling more advanced math texts would be much easier.

“*The Classic of Mathematics* is too hard for beginners, but Ru Tang, don’t give up. I’ll give you a book soon that you’ll definitely understand and learn from.”

Ru Tang asked excitedly, “What’s it called? I’ll ask my parents to buy it for me this afternoon.”

“Don’t rush. The book hasn’t been printed yet. Once it’s ready, I’ll give it to you right away.”

Qiu Huanian thought to himself, not only had the book not been printed, but he hadn’t even written a single word, and the publishing house’s name was still undecided.

During the meal, Qiu Huanian brought up hiring a coachman and shared his requirements.

The other two families, being in business, had extensive experience hiring workers and knew how to hire people in the city. They offered Qiu Huanian some advice.

“Brother Hua, since your carriage needs are fixed, you can hire someone like we do—have them come in the morning and leave in the evening, with a meal at noon. They don’t need to live in your house. Since Mr. Du and his cousin are usually away, having a coachman live in the main house isn’t safe.”

Qiu Huanian had the same thought. “I was also thinking of hiring someone older or younger. Since the work is light, just driving around the city, hiring someone in their prime might bring too many concerns.”

Huang Daniang added, “It’s best to hire someone whose whole family has stable jobs and who has a guarantor. Those with unclear backgrounds might be cheaper, but small households like ours without strong backing can’t afford to take such risks.”

As two women with no relatives to rely on, Huang Daniang and Huang Erniang were extra cautious when hiring, fearing they might bring trouble upon themselves.

“I have a few candidates in mind, Brother Hua. How about this: I’ll ask them tonight and bring any suitable ones to you tomorrow morning for you to check.”

Qiu Huanian agreed and sincerely thanked her. Seeing that the restaurant was getting busy, he didn’t want to disturb their work and took his leave.

The next day, Huang Daniang brought a man in his fifties named Zhou. It was said that in his youth, he had driven long-distance carriages for a carriage company. As he grew older and couldn’t handle the strain anymore, he retired. His driving skills were steady. His son worked as a waiter at Shuyi Inn, and his wife helped with washing and cutting vegetables in the kitchen of Fresh Taste House. The whole family was hardworking and had no bad habits.

After chatting with Old Man Zhou for a while, Qiu Huanian confirmed he was reliable and his experience at the carriage company was genuine, so he hired him.

For four taels of silver a month, including a meal at noon, Old Man Zhou would come every morning to drive Jiu Jiu and Chun Sheng to their respective schools and pick them up in the evening. Occasionally, Qiu Huanian and Meng Yuanling would need him to drive them around, but that was all.

The job was easy, and working for a scholarly family, Old Man Zhou was more than satisfied. He patted his chest, promising to drive the carriage steadily and swiftly.

After adding the coachman’s monthly salary to the accounts, Qiu Huanian looked at the list of expenses and felt a sense of surrealism.

A year ago, when he had just traveled to the Yu Dynasty, his family consisted of only two malnourished children. They had to walk everywhere and work hard with their own hands. The storeroom had only a few pecks of rice and flour, and eating chicken was a rare treat that would make them happy for days.

Now, just a year later, he lived in a refined mansion in the city, owned a carriage, had savings, and employed two people to help with the work. If he wanted, he could spend his days in leisure from morning till night.

Zhu Jingwei sent someone in the morning to deliver the earnings from the red fermented tofu workshop for the last quarter. Red fermented tofu sold even better in winter, bringing in a total of forty taels of silver. Qiu Huanian checked the accounts, stored the silver, and felt his savings grow once again.

He picked up Cream Frost and rocked back and forth on the cushioned lounge chair, stroking the cat from ear to tail, then mischievously rubbing against the grain.

Cream Frost shivered and struggled, jumping onto a nearby chair. She meowed a few times as if scolding him, then curled up and began meticulously licking her fur back into place.

Qiu Huanian lay down for a short while, then resignedly sat up again.

He seemed to be born without the inclination to relax. As soon as he thought of various plans, he was eager to start working on them.

Qiu Huanian went to the study, spread out some cheap bamboo paper for drafting, and first wrote down the words "Basic Math." He then circled them and added terms like "practical," "examples," and "selection."

When it came to basic math, Qiu Huanian, like many modern people, first thought of the "Nine-Nine Multiplication Table," which made countless elementary students weep in frustration but once memorized, it became a lifelong tool.

The Nine-Nine Multiplication Table was not an invention of modern times; it can be traced back to the Spring and Autumn and Warring States periods. Many ancient texts mention it. Besides the Nine-Nine Multiplication Table, the Chinese also invented the decimal system, which spread worldwide over time and became the foundation of global mathematics.

However, this valuable cultural heritage was not yet widely appreciated in the current Yu Dynasty.

Qiu Huanian wrote out the Nine-Nine Multiplication Table from memory in the most common, easy-to-memorize, step-like format and boldly wrote "Memorize" next to it.

All knowledge requires a lot of foundational memorization, and this tool was no exception. Let the people of this world share the pain of modern elementary students!

As he recalled and wrote down these things he had learned in the distant modern world, Qiu Huanian felt happy. After working for a few days, he completed a small chapter just before Jiu Jiu and Chun Sheng went to school.

Qiu Huanian first sent Chun Sheng to the private school, then went with Jiu Jiu to the Zhu family. Jiu Jiu followed Zhu Xian to the elementary school, while Qiu Huanian went to find Su Xinbai.

After Su Xinbai had the idea of starting a bookstore, he had been constantly brainstorming. Many plans were written down, only to be deemed unsuitable and revised again. He had hardly left his courtyard.

Zhu Jingcheng also deliberately brought many tasks home to handle, occasionally visiting the main house.

After noticing that Su Xinbai's attitude toward him had softened, Zhu Jingcheng became bolder and had already started discussing the bookstore's construction with Su Xinbai, offering his own opinions. The two had talked more in the past few days than they had in years of marriage.

When the servants brought Qiu Huanian into the courtyard, Su Xinbai and Zhu Jingcheng happened to be there. The messenger was quick, and upon hearing that Qiu Huanian had arrived, Su Xinbai instinctively stood up from his desk, intending to hide Zhu Jingcheng behind a screen.

Zhu Jingcheng, tugged by Su Xinbai's sleeve, was full of questions, unsure whether to be happy or to cooperate first.

It was too late. Qiu Huanian entered the courtyard and saw the two of them pulling at each other.

Su Xinbai immediately let go as if burned, cleared his throat, and walked out nonchalantly.

Qiu Huanian laughed, "What's going on here? Did I come at a bad time?"

Su Xinbai's expression was blank, his gaze sharp enough to cut through clouds, silently warning Qiu Huanian not to say anything inappropriate. The light pink on his earlobes gradually deepened.

Zhu Jingcheng stepped out a moment later, helping his husband out of the awkward situation, "Brother Hua, are you here to talk about the bookstore with Xinbai? We've already come up with some plans. What do you think?"

Qiu Huanian went along with it, "I also have a new manuscript with me. Let's all have a look."

Behind Zhu Jingcheng, Qiu Huanian gave Su Xinbai a meaningful smile and silently mouthed the word "us."

Su Xinbai's body tensed up, feeling extremely frustrated. He must have lost his mind earlier. Why did he want to hide Zhu Jingcheng just because Qiu Huanian had arrived? It wasn't like they were up to anything improper.

Compared to the bookstore's plans, both Su Xinbai and Zhu Jingcheng were more interested in the new manuscript Qiu Huanian mentioned. As soon as they entered the room, they urged Qiu Huanian to show it to them.

Qiu Huanian handed them the thin manuscript, which had been simply bound with thread.

Both men were well-read and quickly recognized the Nine-Nine Multiplication Table on the first page.

"I remember the ancient text 'Guanzi' mentions, 'An Xi created the Nine-Nine numbers to correspond with the way of heaven,'" Su Xinbai said.

Zhu Jingcheng nodded, "Other books also record it, but most start with 'Nine-Nine Eighty-One' and end with 'Two-Two Four' or 'One-One One.' Brother Hua's way of writing it is the first time I've seen it."

"Although unusual, it is indeed clearer, and the pattern is immediately obvious."

The two of them naturally engaged in a lively discussion.

Qiu Huanian, with a smile on his face, reminded them, "This is a book I wrote to introduce people to mathematics. I've only finished a small chapter so far, with more content to follow. Don't just focus on the first page."

Zhu Jingcheng was puzzled, "Qiu Huanian, why did you think of writing a book on mathematics?"

"While teaching mathematics to children, I discovered some methods on my own. I found that the current texts related to mathematics are too difficult to understand, so I decided to write an introductory book to make it easier for those in need to learn basic mathematics."

"Mr. Zhu, you've been working with mathematics for years, so you must have some strong opinions on this, right?"