ANSWER
EXPLANATION
The given expression is
The middle radical contains a perfect square.
Note that:
#22. We are given that y = 1/4. So, we want to plug this value into the expression 15/y:
15/(1/4)
When you divide by a fraction, you should follow the rule “flip the guy and multiply”. Basically, 15/(1/4) = 15 * 4 = 60.
The answer for #22 is (D).
#23. We can use a proportion:
(The shaded area)/(entire circle area) = (360 - 60)/360
But, we don’t have to find the areas of the region and circle; we can just solve the fraction:
(360 - 60)/360 = 300/360 = 30/36 = 5/6
The answer for #23 is (A).
3/5n - 4/5 = 1/5n....multiply everything by 5 to get rid of the fractions
3n - 4 = n
-4 = n - 3n
-4 = -2n
-4/-2 = n
2 = n <==
