math
posted by anonymus .
you gave this answer toa problem
If you received a $10 reward, then you spent between $50 and $99.99
If you received a $20 reward, then you could have spent $100, $125, or $149.99.
If your purchase is $98, then you'd be better off spending $2 more, so that you'll get another $10 gift card. That would be a net gain of $8, plus the other $10 gift card you got for the first $50 you spent.
but i need to explain how i got this answer. I will not receive full credit unless there is work shown on how to solve the problem

How did you get this answer? I don't know how you got the answer.