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.
Answer:
180
Step-by-step explanation:
its 180 cos its the closest number to 193 that 18 can go in, your overall answer to the equation is 310 remainder 13. But I dont know if u need that..
For my answer i got y = x - 18
Step-by-step explanation:
Subtracting equation (2) from equation (1)
Substituting d = - 3 in equation (1), we find:
Hence, first term is zero.
Answer:
No
Step-by-step explanation:
The formula you could do to check would be 8^2+9^2=12^2.
In this instance, 8^2 + 9^2 = 145 but 12^2 equals 144