Respuesta :

Answer: 4

Step-by-step explanation:

To find out how many boys are in the classroom you must divide 12 from 3 to find the rate of change. 12/3= 4 so then you multiply 1*4 to find out how many boys are in the classroom. 1*4=4

Hope this helps ;)

Answer:

4 boys

Step-by-step explanation:

3:1 is the ratio of girls to boys

Lets girls be g and boys be b

G=3

B=1

G=12     12/3=4 and what you do to one side you do to the other it is multiplied by 4 so

B=1 time 4 =4