Answer:
the total amount she paid for the cake, $82.5
Explanation:
As per the statement:
Melissa bought a cake that cost $75.
⇒Cost of cake = $75
It is also given that:
The sales-tax rate is 10 percent.
then
Sale tax she gave on cake =

We have to find the total amount she paid for the cake.

Substitute the given values we have;

therefore, the total amount she paid for the cake, $82.5