In a classroom of 33 students, the ratio of boys to girls is 3:8. How many boys are in the class?

A:12, since 38 of the students are boys

B:11, since 33 divided by 33 equals 11

C:9, since 3/11 of the students are boys

D:You cannot tell because you do not know the fraction of the total number of students that are boys.

X=number of boys

y=number of girls.

We can suggest the following system of equations:

x+y=33

x/y=3/8

We solve this system of equations by substitution method.

x/y=3/8 ⇒x=3y/8

(3y/8) + y=33

least common multiple=8

3y+8y=33*8

11y=33*8

y = (33*8) / 11

y=3*8

y=24

x+y=33

x+24=33

x=33-24

x=9

number of boys / total number of students=9/33=3/11

There are 9 boys and 24 girls in the class.

Answer: C: 9. since 3/11 of the students are boys.