At Brown Elementary School, 80% of all fifth graders ride the bus to school. If 124 fifth graders ride the bus to school, how many fifth graders are there at school?

Answer:155

Because I had this question before on a test!

Answer: 155 fifth grader students.

Step-by-step explanation:

Given that 80% = 124 fifth grader students, the difference between 80% and total number of fifth grader students is 100% - 80%, which is 20%.

Therefore, if 80/100 = 124

(100/100 - 80/100) = x

We cross multiply:

0.8x = 0.2 x 124

0.8x = 24.8

Divide both sides by 0.8

x = 24.8/0.8

x = 31

Total number of fifth grader students is 124 + 31 = 155