Edgar used 10 x d to represent the number of pennies in d dollars? Is this reasonable?

No.

How many pennies are in a dollar?

100 pennies

To determine if Edgar's representation is reasonable, we need to assess if the conversion between dollars and pennies is accurate.

In the United States, there are 100 pennies in one dollar. So, if we have d dollars, the number of pennies can be calculated by multiplying the dollar amount by 100.

To verify if Edgar's representation is reasonable, we substitute the given representation, 10 x d, in place of d in the calculation. It would look like this:

Number of pennies = 10 x d x 100

Simplifying further, we get:

Number of pennies = 1000 x d

As the resulting representation, 1000 x d, is still in terms of dollars, it would not be reasonable to represent the number of pennies using 10 x d. Instead, the correct representation would be 1000 x d.