Answer :
The amount of peanut butter will be 9 tablespoons.
What is mean by Ratio?
A ratio indicates how many times one number contain in another number. The ratio of two number is written as x : y, which is equivalent to x/y.
Where, x and y are individual amount of two quantities.
And, Total quantity gives after combine as x + y.
Given that;
The ratio to make peanut butter and jelly sandwiches with peanut butter to jelly = 3 : 1
Now,
The ratio of butter to jelly = 3 : 1
So, The amount of peanut butter = 3x
And, The amount of jelly = x
For, the parent uses 3 tablespoons of jelly.
The amount of jelly = x = 3
Hence, The amount of peanut butter = 3x
= 3 × 3
= 9
Thus, The amount of peanut butter will be 9 tablespoons.
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