orange juice

[grandh01]

An incredible punch is composed of
buttermilk, orange juice, and brandy.
How many pints of orange juice are required
to make 7 1/2 gallons of punch
containing twice as much buttermilk
as orange juice and three times as much
orange juice as brandy?

1) 16
2) 18
3) 20
4) 22
5)24

OA IS B

[neelgandham]

Grandh - This doesn't look like a GMAT question. Do you mind citing the source please? I say that because not all know that 1 Gallon = 8 pints. However, assuming that you know the coversion, I will solve it.

Volume of final mixuture = 7.5 gallons = 7.5*8 = 60 pints

Ratio of volume of buttermilk to volume of orange juice = 2:1 = 6:3
Ratio of volume of orange juice to volume of Brandy = 3:1
So, Every 10 parts of punch contains 6 parts Buttermilk, 3 parts Orange juice, 1 part Brandy

For 60 pints of juice, we need (3/10)*60 = 18 pints of Orange juice.