If 15 inches of wire costs 45 cents, that means each inch of wire costs 3 cents. So 12 inches of wire will cost 36 cents.
Answer:
and 
Step-by-step explanation:
We will take numbers to one side and variables to one side eliminate the "Square" with "Square Root" and solve for the variable x. The process is shown below:

Now, we need to reduce the radical by using the rule shown below:

Now,

The correct answer is
and 
<u>Note:</u> squaring positive and negative makes the same answer
Answer:
The distance between the top of the well and the bottom of the well was 12 1/2
Step-by-step explanation:
(a.k.a B) i did it and got it right :)
Answer:
Number of families that should be surveyed if one wants to be 90% sure of being able to estimate the true mean PSLT within 0.5 is at least 43.
Step-by-step explanation:
We are given that one wants to estimate the mean PSLT for the population of all families in New York City with gross incomes in the range $35.000 to $40.000.
If sigma equals 2.0, we have to find that how many families should be surveyed if one wants to be 90% sure of being able to estimate the true mean PSLT within 0.5.
Here, we will use the concept of Margin of error as the statement "true mean PSLT within 0.5" represents the margin of error we want.
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<u>SO, Margin of error formula is given by;</u>
Margin of error =
where,
= significance level = 10%
= standard deviation = 2.0
n = number of families
Now, in the z table the critical value of x at 5% (
) level of significance is 1.645.
SO, Margin of error =
0.5 =

n =
= 43.3 ≈ 43
Therefore, number of families that should be surveyed if one wants to be 90% sure of being able to estimate the true mean PSLT within 0.5 is at least 43.
1,400 it will be 20 qrtly making 80 a year time 5 years