A certain shade of gray paint is obtained by mixing 3 parts of white paint with 5 parts of black paint. 12 gallons of the mixture is needed and the individual colors can be purchased only in one-gallon or half-gallon cans, what is the least amount of paint, in gallons, that must be purchased in order to measure out the portions needed for the mixture?
a)2
b)2 and a half
c)3
d)3 and a half
e)4
the answer is b
please explain. thanks.
a)2
b)2 and a half
c)3
d)3 and a half
e)4
the answer is b
please explain. thanks.
