Question

How many milliliters of pure chocolate must be added to 150 ml of chocolate drink that is 50% chocolate to make a drink that is 75% chocolate?

Answer 1

150 mL pure chocolate.

Explanation:

50% of 150mL means there is 75mL of chocolate in original drink

Let `x` be the amount of pure chocolate to add. Pure/mix=75%

`(75 mL+x)/(150mL+x)=75%`
`(75mL+x)=(150mL+x)*75%`
`(75mL+x)=(112.5mL+0.75x)`
Rearrange to solve for `x`
`0.25x=37.5mL`
`x =150mL`