Answer:
0.998 is the probability that the average money spent by a sample of 40 shoppers is within $10 of the actual population mean.
Step-by-step explanation:
We are given the following information in the question:
Standard Deviation, σ = $21.51
We are given that the distribution of average money spend is a bell shaped distribution that is a normal distribution.
Formula:
We have to find:
P( average money spent is within $10 of the actual population mean.)
Calculation the value from standard normal z table, we have,
The volume of one tissue box is 170 cubic inches, so the volume of 25 tissue boxes are 4250 cubic inches.
3 letters to US = 3*0.94 = 2.82
2 local letters = 2*0.44 = 0.88
checking: 2.82+0.88 = 3.70
to get rid out of 0.04 cents you have to multiply it by 5. so total number of letters would be 5.
First we are going to find the common denominator of both fractions. To do that, we are going to multiply their denominators:
Now we can rewrite our expression using the common denominator:
Finally, we can use the trig identities:
and
to simplify our trig expression:
We can conclude that the correct answer is the fourth one.
