Jenny will get 20 Dirhams when she exchange $5.
The method in which first we find the value of one unit and then the value of the required number of units is known as the Unitary Method.
According to the given question.
For every $1 exchange rate is 4 Dirhams.
Therefore, for $5 the number of Dirhams = 5 × 4 = 20 Dirhams.
Hence, Jenny will get 20 Dirhams when she exchange $5.
Find out more information about unitary method here:
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