SA=4pir^2
78.54km^2=SA
78.54=4pir^2
divide both sides by 4
19.635=pir^2
aprox pi=3.14 so divide both sides by 3.14
6.25318=r^2
sqrt both sides
2.50063=r
round
radius=2.5km
this question is flawed in that it gives the wrong units
answer is the option with 2.5 in it
2nd one
<span>the probability the probability that she will win the prize quilt:
= 15/250
= 0.06
= 6%
</span>
The mean/average is found by adding all of your values and then dividing by the number of values found.
7+7+7+7+7+7+7+7+7+7=70
There are 10 size 7 shoes. Divide 70 by 10 to get the mean, which is 7.
Another ex.
Find the average of numbers listed
1+4+8
these add up to 13
there are 3 numbers listed
13/3=4.33 so the mean is 4.33