Of the 15-year-olds at a karate school, 9 have black belts and 15 have brown belts. among the 16-year-olds, 11 have black belts and 20 have brown belts. which age group has a higher ratio of black belts to brown belts?

15 years olds group had a higher ratio of black belts to brown belts.

Solution:
15 years olds group ratio:

black belts:brown belts
9 : 15
= 3:5
by fraction: 3/5 =1.5

16 years olds group ratio:
black belts:brown belts
11 : 20
by fraction:11/20 =0.55