A school has 63% girls and 37% boys. If 23% of the girls wear contacts and 42% of the boys wear contacts, what percent of all students wear contacts

30.0%

Step-by-step explanation:

0.63*0.23=0.1449≈14.5% approx 14.5%

Therefore, 14.5% of all students at the school are girls who wear contacts.

Let's repeat this for boys by multiplying the percent of boys at the school by the percent of boys that wears contacts.

0.37*0.42=0.1554≈15.5% approx 15.5%

Therefore, 15.5% of all students at the school are boys who wear contacts.

0.145+0.155=0.3=30.0%

30.0% of all the students wear contacts.