8(3980)(5) = 159200
1 mile = 5280 ft
30.15 miles per week
One $10 bill, Two $1 bills, Two Quarters, Two Nickels
Two $5 bills, Two $1 bills, Two Quarters, Two Nickles
One $10 bill, One $1 bill, Six Quarters, Two Nickles
For large sample confidence intervals about the mean you have:
xBar ± z * sx / sqrt(n)
where xBar is the sample mean z is the zscore for having α% of the data in the tails, i.e., P( |Z| > z) = α sx is the sample standard deviation n is the sample size
We need only to concern ourselves with the error term of the CI, In order to find the sample size needed for a confidence interval of a given size.
z * sx / sqrt(n) = width.
so the z-score for the confidence interval of .98 is the value of z such that 0.01 is in each tail of the distribution. z = 2.326348
The equation we need to solve is:
z * sx / sqrt(n) = width
n = (z * sx / width) ^ 2.
n = ( 2.326348 * 6 / 3 ) ^ 2
n = 21.64758
Since n must be integer valued we need to take the ceiling of this solution.
n = 22
2+7= 9
72 / 9 = 8
8 * 2 = 16
<span>8 * 7 = 56
</span>16:56
<span>
Key:
</span>* = times
<span>/ = divide</span>
<span>By dividing the two numbers we get 104.3495... Rounding this number to two decimal places means that we must keep just 2 digits after the "." symbol, and round the last one of them. In our case, 104.3495... becomes 104.35.</span>
