Question

A random representative survey of 100 seventh-graders in Washington Middle School shows that 20 students read 5 or more books over the summer. If there are 275 seventh-graders at Washington Middle School, based on the sample results how many seventh-graders read 5 or more books last summer?

Answer 1

20 out of 100 read 5 or more.

20/100 = 0.2

Now multiply the total students by 0..2:

275 x 0.2 = 55

55 people read 5 or more books.