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.
6 + 0 = 6. Which property:
This is an additive identity or identity property of addition
Answer:
2.50(10) + 3x = 135.97, x = 38.66
Step-by-step explanation:
This should be pretty simple.
Basically, we know that he bought 10 pairs for 2.50 so that's $25 right there.
Our total is 135.97 though-
so here, we take our total from the right side of the equation, and subtract 25 from that.
135.97 - 25 = 115.97
Since he bought three pairs, divide it by 3.
115.97 / 3 = 38.66
One pair of shoes costs $38.66 - hope this helps!
