You can check whether the ratios form a proportion by comparing the ratios in their simplest form.
Yes.
Practice makes perfect
Recall that ratios form a proportion when the ratios are equivalent. Thus, to determine if the given ratios are equivalent, we will rewrite the ratios in their simplest form. If the resultant ratios are equivalent, then the ratios form a proportion.
&15/21=15÷3/21÷3 =5/7 [1.2em]
&55/77=55÷11/77÷11=5/7
Because the resultant ratios are equivalent, 1521 and 5577 form a proportion.
