Answer:
or 1.414
Step-by-step explanation:
1) Find the mean. 1+2+3+4+5 = 15. 15/5= 3
2) For each data point, find the square of its distance to the mean. (4, 1, 0, 1, 4)
3) Sum the values from Step 2. 10
4) Divide by the number of data points. 10/5= 2
5) Take the square root. 
First of all calm down and brake down the problem plan a is $25 a month while the other one is $40 you need to subtract to get $15 than divide $15 by $0.25 which you will get 60 but this is not the right answer because its asking you how many phone calls is the cost of plan b less than the cost of plan a so the answer is 59 calls.
There are no equations there. Only two functions of x.
Answer:
A
Step-by-step explanation:
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