Petrolyn motor oil is a combination of natural oil and synthetic oil. It contains 5 liters of natural oil for every 3 liters of synthetic oil. If 380 liters of natural oil are used, how many liters of Petrolyn oil will be made?
5/3 = 380/x....5 of natural to 3 of synthetic = 380 of natural to x of synthetic cross multiply because this is a proportion (5)(x) = (3)(380) 5x = 1140 x = 1140/5 x = 228 <=== 228 liters of Petrolyn are used
