The equation is true because both sides are identical.
We should find the original number, 7 of 1/10. We divide the known number for the numerator, than multiply for denominator.
7 : 1 = 7 * 10 = 70 <- answer
So 7 is 1/10 of 70
We can check our work:
1/10 of 70 = 7?
70 : 10 = 7*1 = 7
I just took the test and the answer was D
50 in, 48 in, 14 in are the side lengths that form a right triangle