Question

If the divisor is a decimal then you must multiply by a power of 10 to make it a whole number. Why is it important to multiply the dividend and the divisor by the same power of 10?

Answer 1

Sample response: The dividend and the divisor are both multiplied by the same power of 10 so that the answer will be the same quotient as the orgininal problem. Both numbers have to have their decimal points moved to the right the same number of times.

Answer 2

You multiply the divisor and dividend by the same power to keep them within the same ratio of each other.

This applies to non decimal division.

10 / 5 = 2.

If you mutliply both sides by 10 you'd get 100 / 50 which is still 2.

If you only multiplied one side by 10, you could get 100 / 5 which is 20 or 10 / 50 which is 1/5. Both of these mess you the original ratio.