90 students represent x percent of the boys at Jones Elementary School. If the boys at Jones Elementary make up 40% of the total school population of x students, what is x?

A. 125

B. 150

C. 225

D. 250

E. 500

Answer: C. 225

Step-by-step explanation:

To get the total population (x), we will take the 40% of the total population and equate to 90

40% * x = 90

40/100 * x = 90

40x/100 = 90

Cross multiplying,

40x = 100 * 90.

x = 9000/40

x = 225 C