
1. 
HARD

In a class, 20 students are girls, composing 40% of the class. What is the total number of students in the class?

2. 
HARD

In Mr.G's class, the ratio of boys to girls is 4:5. If 25% of the boys leave the class, what is the new ratio of boys to girls?

3. 
HARD

Ben answered 64 problems correctly on his history exam and received a grade 75%. How many problems were on the exam, if all the problems were worth the same number of points? (Round to the nearest whole number)

