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During a sales contest at a local electronics store, 65 empl
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Updated on: 10 Jun 2021, 08:39
Updated on: 10 Jun 2021, 08:39
Expert Reply
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Question Stats:
50% (01:38) correct
50% (02:04) wrong based on 54 sessions
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During a sales contest at a local electronics store, 65 employees sold a total of $91,000 worth of merchandise. If the standard deviation of sales among those employees was $130 and the sales were normally distributed, what percentage of employees sold $1270 or more worth of merchandise?
A. 28%
B. 50%
C. 65%
D. 84%
E. 98%
A. 28%
B. 50%
C. 65%
D. 84%
E. 98%
Drill 3
Question: 11
Page: 530
Question: 11
Page: 530
Re: During a sales contest at a local electronics store, 65 empl
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29 Dec 2017, 15:27
29 Dec 2017, 15:27
1
Expert Reply
Expalanation
Set up your standard bell curve with the proper percentage markers of 2%, 16%, 34% on each side of the central average line. Use an average wheel to find the average sales amount in dollars; you should get 91,000 ÷ 65 = 1400 as the average.
Note that at the 50% mark, and then note the amounts at each deviation above and below the average by adding or subtracting the given standard deviation of $130. Once you’ve filled in the curve, look for $1270 from the question. It is at the 16% mark, indicating that less than 16% of employees sold under $1270 worth of merchandise. Therefore, the other 84% of employees were able to sell $1270 or more worth of merchandise, making choice D the correct answer.
Set up your standard bell curve with the proper percentage markers of 2%, 16%, 34% on each side of the central average line. Use an average wheel to find the average sales amount in dollars; you should get 91,000 ÷ 65 = 1400 as the average.
Note that at the 50% mark, and then note the amounts at each deviation above and below the average by adding or subtracting the given standard deviation of $130. Once you’ve filled in the curve, look for $1270 from the question. It is at the 16% mark, indicating that less than 16% of employees sold under $1270 worth of merchandise. Therefore, the other 84% of employees were able to sell $1270 or more worth of merchandise, making choice D the correct answer.
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Re: During a sales contest at a local electronics store, 65 empl
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15 Jan 2020, 16:39
15 Jan 2020, 16:39
4
sandy wrote:
During a sales contest at a local electronics store, 65 employees sold a total of $91,000 worth of merchandise. If the standard deviation of sales among those employees was $130 and the sales were normally distributed, what percentage of employees sold $1270 or more worth of merchandise?
A. 28%
B. 50%
C. 65%
D. 84%
E. 98%
A. 28%
B. 50%
C. 65%
D. 84%
E. 98%
Drill 3
Question: 11
Page: 530
Question: 11
Page: 530
Mean sales per employee = $91,000/65 = $1400
Standard deviation = $130
$1400 - $130 = $1270
So, $1270 is one unit of standard deviation BELOW the mean.
So when we add all of this information we get the following:
All values to the right of $1270 are greater than $1270
So, the percentage of employees who sold $1270 or more worth of merchandise ≈ 34% + 34% + 14% + 2% ≈ 84%
Answer: D
Cheers,
Brent
