First things you have to do is figure out how much they increased the iPads by:
$50 • 10 = $500
They increased the iPad price by $500.
Subtract the total amount from the iPad price:
$5,000 - $500 = $4,500
The actual price of 10 iPads, without an increase is $4,500
Now divide that by 10 to get the amount for one iPad:
$4,500 ÷ 10 = $450
One iPad actually costs $450 to make.
In addition to mean and sample size you will need the individual scores.
The formula for standard deviation is:
S^2 = E(X-M)^2/N-1
Here's an example:
Data set: 4,4,3,1
Mean: 3
Sample size: 4
First, put the individual scores one after the other and subtract the mean from it.
4 - 3 = 1
4 - 3 = 1
3 - 3 = 0
1 - 3 = -2
Second, square the answers you got from step 1.
1^2 = 1
1^2 = 1
0^2 = 0
-2^2 = 4
Third, plug the values from step 2 into the formula.
S^2 = (1+1+0+4)/(4-1) = 6/3 = 2
Standard deviation = 2
Answer:
4 5/12
Step-by-step explanation:
We need a common denominator of 12
4 3/4 = 4 3/4 *3/3 = 4 9/12
1/3 *4/4 =4/12
4 9/12 - 4/12 =4 5/12
