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For which of the following months does the average monthly high temper
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17 May 2021, 13:10
17 May 2021, 13:10
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30% (02:26) correct
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For which of the following months does the average monthly high temperature for City X fall within one standard deviation of the average annual high temperature?
Indicate all such months.
January
March
May
July
September
November
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Official Answer
B,C,E,F
Re: For which of the following months does the average monthly high temper
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19 May 2021, 00:33
19 May 2021, 00:33
any explanations on how to solve this question?
Re: For which of the following months does the average monthly high temper
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19 May 2021, 00:41
19 May 2021, 00:41
3
Expert Reply
OE
One standard deviation captures 68% of the data points, or 34% in each direction from the mean. For this question, that means that 68% of the months of the year will have average high temperatures within one standard deviation of the annual average high temperature. 12 × 68% = 8.16, so 8 months will be within one standard deviation. Standard deviation assumes a “normal” (balanced on the high and low ends) distribution, so the 2 months with the greatest average monthly high temperature and the 2 with the lowest average monthly high temperature will fall outside of one standard deviation. To answer the questions, use POE to eliminate the 2 most extreme months on each end.
It is clear that January has the lowest average high temperature, so eliminate choice (A). February probably comes next, but it doesn’t matter since neither it nor December is an answer choice. November is definitely not one of the two months with the lowest average high temperatures, so choice (F) is in. July has the highest average high temperature, so eliminate choice (D). Whether June or August is second doesn’t matter for us because neither is an answer choice, but that means March, May, September, and November all make the cut.
One standard deviation captures 68% of the data points, or 34% in each direction from the mean. For this question, that means that 68% of the months of the year will have average high temperatures within one standard deviation of the annual average high temperature. 12 × 68% = 8.16, so 8 months will be within one standard deviation. Standard deviation assumes a “normal” (balanced on the high and low ends) distribution, so the 2 months with the greatest average monthly high temperature and the 2 with the lowest average monthly high temperature will fall outside of one standard deviation. To answer the questions, use POE to eliminate the 2 most extreme months on each end.
It is clear that January has the lowest average high temperature, so eliminate choice (A). February probably comes next, but it doesn’t matter since neither it nor December is an answer choice. November is definitely not one of the two months with the lowest average high temperatures, so choice (F) is in. July has the highest average high temperature, so eliminate choice (D). Whether June or August is second doesn’t matter for us because neither is an answer choice, but that means March, May, September, and November all make the cut.
