# How many gallons of 4% milk should you mix with 1% milk to make 10 gallons of 3% milk?

Apr 17, 2018

$6 \frac{2}{3}$ gallons of 4% milk to be mixed with $3 \frac{1}{3}$ gallons of 1% milk to make $10$ gallons of 3% milk.

#### Explanation:

Let $x$ gallons of 4% milk is mixed with $\left(10 - x\right)$ gallons of

1% milk to make $10$ gallons of 3% milk.

Equating milk content , we get ,

$x \cdot 0.04 + \left(10 - x\right) \cdot 0.01 = 10 \cdot 0.03$ . Multiplying by $100$ on

both sides we get , $4 x + 10 - x = 30 \mathmr{and} 3 x = 20$

$\therefore x = \frac{20}{3} = 6 \frac{2}{3} \therefore 10 - x = 10 - \frac{20}{3} = \frac{10}{3} = 3 \frac{1}{3}$ Hence,

$6 \frac{2}{3}$ gallons of 4% milk is mixed with $3 \frac{1}{3}$ gallons of

1% milk to make $10$ gallons of 3% milk. [Ans]