In this question, the thing that needs to be found is the number whose 20% would be 18. The information's required for getting to the solution are already provided in the question. based on those given information's, the answer can be deduced very easily.
Let us assume the unknown number to be = x
Then
(20/100) * x = 18
x/5 = 18
x = 18 * 5
= 90
so the unknown number in the question is 90. I hope the procedure is clear enough for you to understand.
I am not completely sure but Khan Academy might show how to do that. Or it might at least give an example.
answer: you're missing the problem
Answer:
475 km
Step-by-step explanation:
(40 + 45 + 50 + 35 + 55 km + 50 *5 km)
<span>I believe the answer is 60.75pi, calculated as follows:</span>
Area of Circle: (9 * 9) * pi = 81pi
Area of Shaded Area = (90 / 360) * 81p = 20.25pi
81pi - 20.25pi = 60.75pi