Step-by-step explanation:
first you have to use the formula for circle is 2πr
22
π= ----
7
and r stands for radius
Answer:
1.5 per hour : 1.2 per hour
Step-by-step explanation:
The computation of the ratio is shown below:
For norma, the one pool would be
= 12 pools ÷ 8 hours
= 1.5 per hour
And for albert, the one pool would be
= 9 pools ÷ 7.5 hours
= 1.2 per hour
So the ratio between them is
1.5 per hour : 1.2 per hour
The mean of the data is 11
now we find the difference between the mean and each number
1, 2, 3, 0.5, 0.25, 1.25, 1.
now we square the numbers
1, 4, 9, 0.25, 0.0625, 1.
now we find the mean of the new numbers
which is 2.1875
2.1875 is your standard deviation.