2. The second item of a arithmetic progression is 2.8 and the third item is 3. 1. Find the 15 term of this arithmetic progression.
There are 36 students in Class Two, Grade Five. Wu Hong, the monitor, is going to buy a picture book for everyone. I forgot to count the money when I came back, but I only remembered that it was ◇ 1. 1 □ yuan. Q: The unit of each picture is yuan.
4. The stock oil of Dongyou is 6 times that of Xiyou. If the two oil depots add 30 tons of oil each, the stock oil of Dongyou will be three times that of Xiyou. How many tons of oil were originally stored in these two oil depots?
5, a six-digit KABCDEK, multiplied by E, the original number is ABCDE, what is the original number? (Different letters represent different numbers) What was the original number?
6. 500 people from qingquan primary school attended the entrance ceremony of the sports meeting. Every 20 people walk in a row, the distance between two rows is 3 meters, and the podium 18 meters. How many minutes does it take them to pass the podium at a speed of 30 meters per minute?
8,5/7 can be converted into cyclic decimals. What is the number1995th after the decimal point of this cycle decimal? What is the number?
9. The three sides of a triangle are three consecutive two-digit even numbers, and the sum of their mantissas can be divisible by 7 to find the maximum circumference of this triangle.
10. There is a score. If you add 1 to both the numerator and denominator, the score becomes 1/2. If both the numerator and denominator are subtracted by 1, the score becomes 2/5. Find this score.
1 1. One day, tens of thousands of diamonds were stolen from a jewelry store in a city. After reporting the case, after three months of investigation, it was found that the perpetrator was definitely one of A, B, C and D. After trial, the confessions of these four people were as follows:
I was in another city the day the diamond was stolen, so I'm not a criminal.
Ding is a criminal.
C: B is a thief. I saw him selling diamonds on the black market three days ago.
D: B bears a grudge against me and deliberately sets me up.
Because the confession is inconsistent, it is impossible to determine who is the criminal.
After the polygraph test, I learned that only one of these four people was telling the truth, so who was the criminal?
12. There are 253 students in Grade 5 of Qingfeng Primary School. The school organized a math group, a recitation group and a dance group. It is stipulated that everyone should participate in at least one group and at most two groups. How many people should participate in the same group?