Question

A school has 60% girls and 40% boys. If 20% of the girls wear glasses and 40% of the boys wear glasses, what percent of all students wears glasses?

Answer 1

Determine the percentage of girls wear glasses compared to all students.
g = 20% × 60%
g = 20/100 × 60/100
g = 1,200/10,000
g = 12/100
g = 12%

Determine the percentage of boys wear glasses compared to all students.
b = 40% × 40%
b = 40/100 × 40/100
b = 1,600/10,000
b = 16/100
b = 16%

Calculate the percentage of students wear glasses
s = 12% + 16%
s = 28%
The students wear glasses is 28%