1. says that 1 standard deviation above and below the mean ranges from 7 to 13. Calculate the range. Range=6.
Now, standard deviation for a set is constant. Let us draw a number line.
---------|----------------|---------------|------------------ -m mean +m
In this line segment, mean is at the center and the distance between 2 equal points -m and +m from mean is 6. These two points are equidistant as they are mentioned to be one standard deviation above and below the mean. Hence, the range of values between them=2m
2m=6
Hence, m=3
Hope this clarifies any doubts!
Sachin9 wrote:
watwazdaquestion wrote:
smartass666 wrote:
Given that the mean of Set A is 10, what is the range of two standard deviations above and below the mean?
(1) One standard deviation above and below the mean ranges from 7 to 13.
(2) The median of set A is 11.
1. standard deviation = 3 since mean = 10... 3 units below and 3 units above. can calculate range of 2 standard deviations above and below mean by: 10-6 = 4 and 10+6 = 16... range of 2 standard deviations above and below mean = (4, 16)
2. gives no information on standard deviation. insufficient.
answer is A
how did u calculate the standard deviation to be 3?
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