Using proportions, it is found that the unit rate is of 1.33 cups of brown sugar for a batch of cookies.
A proportion is a fraction of a total amount, and the measures are related using a rule of three.
2/3 cups of brown sugar are used for half a batch of cookies. The unit rate is the amount used for one batch. Hence, the rule of three is given by:
2/3 cups - 1/2 batch
x cups - 1 batch.
Applying cross multiplication:
[tex]\frac{1}{2}x = \frac{2}{3}[/tex]
[tex]x = \frac{4}{3}[/tex]
The unit rate is of 1.33 cups of brown sugar for a batch of cookies.
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