Lenny is making his own laundry soap. The recipe calls for 2 parts borax, 2 parts washing soda, and 1 part soap flakes. If Lenny uses 7 cups of soap flakes, how many cups of borax and washing soda combined does he need?
Cross multiply
Divide
To find out how many cups of borax and washing soda combined Lenny needs, we need to first determine the ratio between the soap flakes, borax, and washing soda.
According to the recipe, there are 2 parts of borax for every 1 part of soap flakes. This means that for every 2 cups of borax, there is 1 cup of soap flakes.
Similarly, there are also 2 parts of washing soda for every 1 part of soap flakes. This means that for every 2 cups of washing soda, there is 1 cup of soap flakes.
Since Lenny is using 7 cups of soap flakes, we can determine the amount of borax and washing soda needed by multiplying 7 cups by the ratios.
For borax:
7 cups soap flakes * (2 cups borax / 1 cup soap flakes) = 14 cups of borax
For washing soda:
7 cups soap flakes * (2 cups washing soda / 1 cup soap flakes) = 14 cups of washing soda
Therefore, Lenny needs a total of 14 cups of borax and 14 cups of washing soda combined.