Question

Petrolyn motor oil is a combination of natural oil and synthetic oil. It contains 5 liters of natural oil for every 7 liters of synthetic oil. In order to make 672 liters of petrolyn oil, how many liters of natural oil is needed?

Answer 1

`(5)/(13) = (x)/(672)`

`13x=5*672`
`13x=3360`
x=258.5 L of natural oil