Why is 3/7, and 12/21 non-proportional

If two fractions are proportional, what you do to the denominator, you must do also to the numerator.

In this case, 3/7 and 12/21 is non-proportional, because the numerator was multiplied by 4 (3 x 4 = 12) , while the denominator was multiplied by 3 (7 x 3 = 21). If it was proportional, both the numerator and denominator must be multiplied by either 3 or 4.

~

.632

step-by-step explanation:

6 * 1/10 = 3/5

3*0.01 = 0.03

3/5 + 0.03 = .63

2*0.002 = .002

.63 + 0.002 = .632