Answer:
21:A 22:D
Step-by-step explanation:
hope that helps
One way you could solve this is to just multiply the top and bottom out so that you get 9/81, reducing it by 9/9 to get 1/9 or option C.
Another way would be to do

since dividing numbers with exponents would be subtracting the bottom exponent from the top exponent, provided that the base number (in this case 3) is the same for both. For this method, you would get

, which is equal to 1/9 or .1 repeating, the same answer that you'd get with the first method.
Answer:
Nope! these ratios do not form a proportion
Step-by-step explanation:
if you use a calculator to divide 10/9, you get 1.111 repeating.
if you use a calculator to divide 17/15, you get 1.133 repeating.
<em>since 1.111 does not equal 1.113, </em><em>these ratios are not proportional. </em>
It will equal 22.5 since you need to multiple