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Re: Set S: {5, 10, 15} If the number 15 were removed from set S
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12 Aug 2018, 16:14
Explanation
The word mean is a synonym for the average. Because an average is calculated by taking the sum of the terms in the set and dividing by the number of numbers in the set, changing any one number in a set (without adjusting the others) will change the sum and, therefore, the average.
The median is the middle number in a set, so making the biggest number even bigger won’t change that (the middle number is still 10). Standard deviation is a measure of how spread out the numbers in a set are—the more spread out the numbers, the larger the standard deviation—so making the biggest number really far away from the others would greatly increase the standard deviation.