Question

Petrolyn motor oil is a combination of natural oil and synthetic oil. It contains 6 liters of natural oil for every 5 liters of synthetic oil. In order to make 847liters of Petrolyn oil, how many liters of natural oil are needed?

Answer 1

If you have 6x liters of natural oil, then you have 5x liters of synthetic oil. (It doesn't matter what x here stand for). Thus, you have 6x+5x=11x liters of Petrolyn motor oil.
If we have 847 liters of Petrolyn oil, then 11x=847 which means x=77 and 6x=462 liters of natural oil is needed.

Answer 2

Thank you ! :P

Answer 3

No problem. :D