Answer:

Step-by-step explanation:
-For a known standard deviation, the sample size for a desired margin of error is calculated using the formula:

Where:
is the standard deviation
is the desired margin of error.
We substitute our given values to calculate the sample size:

Hence, the smallest desired sample size is 23
The price of album y is $5.80. I solved the system of equations of B and C. Getting rid of the variable z, I was able to get rid of x next. Solving this system gave me $5.80 without having to substitute into the other equation.
In order to write 25 letters in 4 days you would need to write 6.25 a day
Type into your calculator (if you haven't already): log 54.
My result: was similar to yours.
Note, however, that we're supposed to round off these results to the nearest thousandths (not thousand).
Your 1.73239 would need to be rounded off to 1.732, with 2 being the nearest thousandths.
Answer:
Amount used by the end of the second week= $500-$375
=$125
Amount used by the end of the seventh week= $375-$100
=$275
Total amount spent= $275+$125
=$400
Rate of change= $ 500- $400
=$ 100
Step-by-step explanation: Hope this helps