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.
<u></u>
<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:
She spent 8 dollars.
Step-by-step explanation:
24 divided by 3 is 8
I need a little bit more detail in order to answer your question properly
The mean age of the frequency distribution for the ages of the residents of a town is 43 years.
Step-by-step explanation:
We are given with the following frequency distribution below;
Slope-intercept form:
y = mx + b
"m" is the slope, "b" is the y-intercept
To find "m", you can use the slope formula and plug in the two points:




The slope is 0 so:
y = mx + b
y = 0x + b [any number multiplied by 0 is 0]
y = b
To find "b", you plug in either of the points into the equation (since both of their y values are 1]
y = b
1 = b
Your equation is:
y = 1 (This is a horizontal line)