A mother is making her own bubble mix out of dish soap and water for her two-year-old son.  The recipe she is following calls for 3 tablespoons of soap for every 1 cup of water.  If the container she hopes to store the bubble mix in can hold 40 ounces of liquid, and there are 8 ounces in a cup of water, how many tablespoons of soap should she add to the container (assuming that the soap itself doesn't count towards the capacity of the container)?
How many cups of water can the container hold? ** The 40-ounce container can hold 40/8 = <<40/8=5>>5 cups of water.
How many tablespoons of soap should be used? ** This means that 5*3 = <<5*3=15>>15 tablespoons of soap should be used, since each cup of water requires 3 tablespoons of soap.
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