A school has a ratio of 3 to 8 for boys to girls. If there are 132 students in the class, how many of them are boys?

36 boys.

Step-by-step explanation:

The ratio of boys to the total is

3/11.  Where did that 11 come from? You add the two components of the ratio to get the ratio of one of the genders to the total.

boys / total = 3 /(8 + 3) = 3/11

3/11 = x / 132           Cross multiply

3 * 132 = 11x            Divide by 11

3 * 132/11 = 11x/11     Simplify\

3 * 12 = x

x = 36

5

step-by-step explanation:

1) c 2143.6 cm

2) c 113.0 m

3) a 33.5 ft

4)   d 2 cm

5) c 20 mm

6) 180 in

7) d 120 ft