Question #8ab21

1 Answer
Dec 8, 2017

#2:1#

Explanation:

For simplicity, suppose there are #3x# girls and #2x# boys, where #x# is an arbitrary number. After 25% boys leave the group, remainder is:

girls : #3x# (no change)
boys: #2x - 25% # of #2x = 2x *(1 - 0.25) = 1.5 x#

New ratio of girls to boys is # \frac{3x }{1.5 x} = 2:1 #