② 100×25% means that the number of class two is 25% of that of class one;

③ 100÷( 1+25%) indicates the number of people in Class Two.

So the condition is: How many students are there in Class Two?

(4)100× (1-25%) means that there are 25% fewer students in Class Two than in Class One;

⑤ 100÷25%;

⑥ 100×( 1+25%) means how many people are there in the two classes?

2. The drawings are as follows:

Question1:How many people are there in Class 60 B than Class A?

Question 2: How many people have a score of 60 or above in Class A?

Question 3: Which score is the biggest difference between Class A and Class B?

Question 4: In which fraction segment are the numbers of Class A and Class B closest? How many people are there?

Question 5: In paragraph 70, what is the number of class A compared with that of class B?

1, 5-2=3 (person);

2,4+6+15+23 = 48 (person);

The number of people with different scores above 3.90 is the largest;

The number of people above 4.60 has the smallest difference, which is1;

5、6÷ 10=35.

So the answers are: 1, ① (100-80) ÷100×100%, ② The number of students in Class Two is 25% of that in Class One, ③ How many students are there in Class Two? ④ There are 25% fewer students in Class Two than in Class One; ⑤ 100÷25%; ⑤ How many students are there in Class Two?