Answer:
A)
Note that
Lower Bound = X - z(alpha/2) * s / sqrt(n)
Upper Bound = X + z(alpha/2) * s / sqrt(n)
where
alpha/2 = (1 - confidence level)/2 = 0.025
X = sample mean = 1723.4
z(alpha/2) = critical z for the confidence interval = 1.959963985
s = sample standard deviation = 89.55083319
n = sample size = 30
Thus,
Lower bound = 1691.355235
Upper bound = 1755.444765
Thus, the confidence interval is
( 1691.355235 , 1755.444765 ) [ANSWER]
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b)
We assumed taht the distirbution of these observations is approximately normally distributed.
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c)
Yes, because the values are not far away from each other.
The answer to the question above is the first one
They are looking for the y intercept. The line of best fit passes the y axis at 1. the y axis is labeled minutes stretching. therefore the answer is
A. <span>1 minute; the number of minutes students stretch when they do not jog</span>
Invested at 3% = x
invested at 4% = 2x
invested at 5% = x+500
0.03x + 0.04(2x) + 0.05(x+500) = 2025
0.03x + 0.08x +0.05x +25 = 2025
0.16x = 2000
x= 12,500
4% = 2x = 12,500 * 2 = $25,000
