The delivery times for all food orders at a fast-food restaurant during the lunch hour are normally distributed with a mean of 1
1 answer:
Answer:
estimated sample mean X is 14.7 minutes
sample standard deviation is ≈ 0.59 minutes.
Step-by-step explanation:
Let X be the mean delivery time for a random sample of 40 orders at this restaurant, then
X can be estimated as 14.7 minutes (mean delivery time for all food orders at a fast-food restaurant during the lunch hour)
Let s be the standard deviation of delivery time for a random sample of 40 orders at this restaurant, then
≈ 0.59 where
- 3.7 is the standard deviation of the delivery times for all food orders at a fast-food restaurant during the lunch hour
- 40 is the sample size
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Answer:
Step-by-step explanation:
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I don't see this but what happens if we find a common denominator for those 2 terms after the square. (b/2a)^2=b^2/4a^2 so we need to multiply that one fraction by 4a/4a.
They put it in ( )
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