-10 because if you flip it 7-10=-3
Answer: OPTION D.
Step-by-step explanation:
You have the expressions given in the problem:

To find the product of both expression you must multiplicate them.
You must multiply the numerators of both expression and the denominators of both expression.
Keeping the above on mind, you obtain that the product is:


Julie traveled 3 times more miles than Danny.
This is because 24x is 3 times more than 8x and -63 is 3 times more than -21.
The answer to your question is .........