# Jennifer made a fruit juice using red and green grapes. Thirty percent of the grapes are green. If she used a total of 60 grapes, how many red grapes should she use?

Jul 31, 2016

$42$

#### Explanation:

If 30% if the $60$ total grapes are green, then 100%-30%=70% of the grapes are red. To find the total number of red grapes, then, we must calculate 70% of $60$. We do so by multiplying $60$ by 70%=70/100.

$\text{Total red grapes} = 60 \times \frac{70}{100}$

$= \frac{60 \times 70}{100}$

$= \frac{4200}{100}$

$= 42$

Thus she used $42$ red grapes.