At camp Wonka, there are 96 campers.  Two-thirds of the campers are boys, and the remaining one-third are girls.  50% of the boys want to toast marshmallows and 75% of the girls want to toast marshmallows.  If each camper gets one marshmallow to toast, how many marshmallows do they need?
The girls make up one-third of the campers, so there are 96 /3 = 32 girls.
The boys make up two-thirds of the campers, so there are 32 + 32 = 64 boys.
There are 32 x 75% = 24 girls who want to toast marshmallows.
There are 64 x 50% = 32 boys who want to toast marshmallows.
They need 24 + 32 = 56 marshmallows.