1. Xiao Qiang and Xiaogang went to the book fair and saw an English-Chinese dictionary. Both people want to buy it, but the money in Xiao Qiang is 1 1 yuan, and that in Xiaogang is 14 yuan. If they buy one, the dictionary is left with 8 yuan (33 yuan).

Strong band 14+8=22 yuan, just with 1 1+8= 19 yuan.

Book price: 22+ 1 1=33 yuan.

2. Class A and Class B have 10 1 students, and the sum of Class A 1/4 students and Class B 2/7 students is 27 students, so Class A has (52) students.

A /4+2/7×( 10 1- A) =27。

A =52 people

3. In a class meeting, the number of people asking for leave is 65438+ 0.9 of the attendance, and there is another person asking for leave in the middle, so the number of people asking for leave is 3/22 of the attendance, so this class has (50).

1÷ (110-3/25) = 50 people

4. Buy a B card and pay A yuan (A and B are natural numbers). The salesperson said, "If you buy more 10 cards, I will always charge you 2 yuan, which is equivalent to saving 2 yuan by buying 30 cards." Then, a = 1 and b = 5.

a= 1

1/b×30-2 = 60/(b+ 10)×30

b=5