Answer:
a = 14
Step-by-step explanation:
The mean is the sum of the values divided by the number of values.

Answer:
x = ± 
Step-by-step explanation:
Given
x² = 20 ( take the square root of both sides )
x = ± 
which can be simplified to
x = ± 2
[ ± means plus or minus ]
1/5 five being the denominator, because in math you must always simplify
If you do 5 divide by 4 then you can find what 1$ would be worth so ie.
5 divide by 4 is 1.25 which means that for 1$ you could buy 1.25 ounces