Remember, the volume formula of a sphere is

.
Set that equation equal to whatever volume they give you and solve for r.

=

Now solve for r! I know you can do this. If you need help, just comment.
Answer:
Step-by-step explanation:
Use the following formula:
slope: 
Let:

Plug in the corresponding numbers to the corresponding variables:

is your answer.
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If there are 189 children, then there are 189 divided 7 = <em>27 groups of 7 children.</em>
As mentioned in the problem,<em> for every 7 children, there are 2 caretakers </em>therefore, there are a total of 2 x 27 = 54 caretakers in the local daycare.
So, in total, there are 189 children + 54 caretakers = 243 people in the daycare facility.
When trying to find a percent, it is best to multiply everything by 100 (as a percentage is out of 100). 0.03*100= 3 and 1*100=100. Therefore, 0.03 as a percent is 3%
Hope this helps :)
33: 21 ...........................................