Which ratio has the same unit rate as 15 : 9? A. 9 : 5

B. 10 : 6

C. 16 : 10

D. 25 : 18

In a fifth grade class, 3/5 of the girls have brown hair. of the brown-haired girls, 3/4 of them have long hair. of the girls with long brown hair, 1/3 of them have green eyes. what fraction of the girls in the class have long brown hair?