Answer: C) 12
Explanation:
4:3= 4 boys per 3 girls
16: x= 16 boys to x girls
Since Sean wants there to be 16 boys, he has to divide 16 boys by the ratio of 4.
You will get 4, and now you multiply 4 by the ratio of 3 girls.
In other words, 4 times 3 is 12, so he will need 12 girls to go to his party to keep a 4:3 ratio.
Hope this helped!