Question

in ronnas class, the ratio of boys to girls is 2:3. in suzies class, there are half as many girls as in ronnas class. if there are 12 boys in ronnas class, how many girls are in suzies class?
a 18
b 9
c 8
d 36

Explanation:

Step1: Find girls in Ronna's class

The ratio of boys to girls in Ronna's class is \(2:3\). Let the number of boys be \(2x\) and girls be \(3x\). Given boys \(= 12\), so \(2x = 12\), then \(x = 6\). Number of girls in Ronna's class is \(3x = 3\times6 = 18\).

Step2: Find girls in Suzie's class

Suzie's class has half as many girls as Ronna's. So girls in Suzie's class \(=\frac{18}{2}=9\)? Wait, no, wait, maybe I miscalculated. Wait, ratio boys:girls = 2:3. Boys are 12, so 2 parts =12, 1 part=6. Girls are 3 parts=18. Then half of 18 is 9? But the options have 9? Wait the options: A.18, B.6, C.9, D.36. Wait, maybe I made a mistake. Wait, ratio 2:3, boys 12. So 2/3 = 12/girls in Ronna. So girls in Ronna = (12×3)/2 = 18. Then Suzie's girls are half of 18, which is 9. So the answer should be C.9.

Answer:

C. 9