Answer:
Step-by-step explanation:
The standard deviation is the square root of the variance, and the variance is found by using the mean. So we will do that first. I will use the population variance as opposed to the sample variance since our set of numbers is small.
The mean: 8 + 12 + 15 + 17 + 18 = 70 and divide that by 5 to get
and use this to find the variance in the formula:
it is a bit difficult to enter that formula in correctly, but here's how it works mathematically:
Squaring this ensures us that we don't end up with zero, which would be useless.
so
which means that the standard deviation is
s = 3.633
(If you do it with n-1 = 4 in the denominator of the variance, you get a standard deviation of 4.062)
Answer:
It would take him 450 minutes to burn off the calories by sleeping
Step-by-step explanation:
Answer:
q = 3 + 1/2r
Step-by-step explanation:
10q - 5r = 30
We want to solve for q
Add 5r to each side
10q - 5r+5r = 30+5r
10q = 30+5r
Divide by 10
10q/10 = 30/10 +5r/10
q = 3 + 1/2r
Answer:
A'=(5/2,-5/2)
therefore A'(2.5,-2.5)
Step-by-step explanation:
Step-by-step explanation:
$20/hr carpenter pay
$25/hr blacksmith pay
Let c = hours working carpentry
Let b = hours working as blacksmith
c + b = 30 {equation 1}
20c + 25b = 690 {equation 2}
In equation 1 solve for one variable in terms of the other.
c = 30-b
Substitute that into equation 2:
20(30-b) + 25b = 690
600 - 20b + 25b = 690
5b = 90
b = 90/5
b = 18 hours working as a blacksmith
c = 30-b = 30-18 = 12 hours as a carpenter
