Huo Yanran didn't have anything important to find Xia Yu, it was just a normal dinner appointment between girlfriends, and they hadn't had time to meet for a while, but they didn't expect to meet Xia Yu after the exam, so they picked up Yang Yan and Luoluo.

"How did you do in the exam?" Huo Yanran teased for a while, then finally turned her head and asked with concern.

"It's okay, all the questions in the morning are done, and then the interview in the afternoon, I don't know this, the scoring standard is in the examiner. Xia Yu put down the cup of water and replied.

"How are you answering those math questions in the line test?Are you sure?" Yang Yan hadn't asked Xia Yu these questions yet, and at noon, he was worried about affecting Xia Yu's interview status in the afternoon, so he didn't mention a word, but he was still more concerned about this issue, because according to the previous civil service exams he had collected, the questions in the math part would be the key to getting points!

"It's basically done, but fortunately, you told me about those quick calculations and other skills!" Xia Yu glanced at Yang Yan gratefully, and then fell into the memories of hard work, "However, there is a question that I have Meng, and the topic is: 10 consecutive ...... Odd, not, is even, and the sum of even numbers is the sum of 10 consecutive odd numbers starting with 1...... 2.5 times, it asks what the largest even number is. ”

When Xia Yu reviewed with Yang Yan, what averages, permutations and combinations, and probability issues were all involved, but Xia Yu had the impression that Yang Yan had not told her about odd or even numbers.

"At the beginning, I counted directly, 1, 3, 5, 7, 9...... I forgot that I could use that equal difference series, but then I was worried that I didn't have enough time, so I got an A option, because I thought that the middle number was more average, 2.5 times 9 is 22.5, and to the largest even number, it should be about 34.5, 34 is closer. Xia Yu rushed to tell Yang Yan how she solved this problem, and after finishing speaking, she still looked at Yang Yan with a blank eye, and wanted Yang Yan to tell her that she was not mistaken.

Although it was only a selective exam, once Xia Yu made up her mind to take the exam, she really spent a lot of thought and energy to review, so Xia Yu felt that every point was very important.

However, Yang Yan listened to her answer, and a smile appeared on his face, and he said with a smile: "I found that you are becoming more and more mathematically minded now!"

Xia Yu already vaguely felt that she might be right, but Yang Yan never gave a positive answer, which made her a little crazy.

"Hey, when is it, you're still selling guanzi here?" Xia Yu was so anxious that she couldn't help but stomp her feet under the table.

"I mean you're right! Moreover, your idea of using the median value to solve is also right!" Yang Yan took a napkin on the table, then took out Xia Yu's exam pen from his bag, and wrote the formula with her, "This problem is actually a problem for solving equations in a series of equal differences!"

"Starting from 1, 10 consecutive odd numbers, the sum of them is: (1+1+9X2) divided by 2, let's not care what the result is, let's first look at the sum of the other ten consecutive even numbers, the same way, its summing formula is, wait a minute, let's assume that the first even number is x, then this formula is (x+x+9X2) and then divided by 2!" Yang Yan wrote on the tissue, Xia Yu, a good student, also put his head close together and listened intently.

What are Mom and Dad doing?

Luoluo, who was sitting on the other side with her aunt, couldn't see what her father was writing, and of course, she couldn't understand the "complicated" formulas that her father said, but she couldn't hold back her curiosity, so she still propped up the sofa, stood up on the sofa, and put her two little hands on the table.

"Be careful, don't climb up!" Huo Yanran hurriedly hugged Luoluo's weak waist, hugged her back, let her little butt sit in her arms, and said softly, "You can't move around in this public place, you know?

Luoluo still had a strong interest in what her father and mother were doing, and she hummed and stretched out her little hand, not listening to what her aunt said.

Putting aside Luoluo's side for the time being, Yang Yan's solution idea is very clear and fast, he quickly crossed out the same terms in the two formulas, such as dividing by 2, and multiplying 2 in parentheses, as well as the same number (symbol), and finally only (1+9) and (x+9) remained, and the interval between them was multiplied by 2.5!

"Here, you see the odd number in front of you, and the rest is 10, which is actually about the middle number 9 you said, but in fact, there are 10 odd numbers, and there should be 9 and 11 in the middle, and their average number should be 10. Yang Yan smiled and said, "However, it doesn't matter, because the results are the same, the x found here is 16, and when it comes to the fourth number, it is 22, which is not much different from the 22.5 you said." ”

Therefore, although Xia Yu is a blind shortcut algorithm, in fact, she still got the right direction, so she also calculated the correct value!

Of course, Yang Yan did calculate it quickly, and explained it to Xia Yu very clearly, but Xia Yu was not able to get around these formulas at once, she picked up the napkin written by Yang Yan and was still looking at it carefully.

Huo Yanran couldn't look at it anymore, she complained: "I've finished the exam, what else do I want to see? Yang Yan said so much, I only remember one sentence, Xia Yu, she got the question right!"

"Hurry up, order, order!" Huo Yanran beckoned the waiter to bring the menu, and at this time, Xia Yu put down the tissue.

Huo Yanran ignored Yang Yan and Xia Yu, a serious couple who loved to drill the "tip of the horns", she spread out the menu in front of Luoluo, and asked with a smile: "Luoluo, look, what do you like to eat?"

The colorful menu, relying on the beautiful food photos, immediately attracted Luoluo's attention, and the little girl didn't care to explore the things that her father and mother were studying, so she looked at the menu with great interest.

However, in a Western restaurant, especially in this one, which is a very high-grade Western restaurant, there are not many dishes on the menu, and there are also appetizers, soups, side dishes, and so on! Huo Yanran flipped through several pages, and she couldn't finish reading them.

"Hmm......" The little girl couldn't help it, and her fleshy little palm pressed on the menu, otherwise the aunt would turn the page.

People haven't finished reading it yet!

"What, do you want this French baked onion soup?" Huo Yanran asked funny, she was actually teasing Luoluo, and she didn't see that Luoluo had obvious intentions for this dish.

However, to Huo Yanran's surprise, the little girl raised her little head, looked at herself, and quickly pursed her little mouth, nodding her head, and muffled "um".

"Okay, then what else do you want?" Huo Yanran looked at the little guy with interest.

What do you want?

Luoluo wants a lot!

I saw Luoluo put her eyes back on the menu with a lot of beautiful color photos, her little hand pressed on it, swept it one by one, her small mouth pouted, and said in a milky voice: "Jie, Jie, Jie......"

"Then, don't you want any of these?" Huo Yanran thought of a joke and couldn't help laughing.

Luoluo wasn't joking with her aunt, she blinked her eyes wide, and said with a serious expression: "No, it's not a vegetarian!