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by sud21 » Thu Jan 12, 2012 2:59 am
Set S and T have 100 numbers, respectively. Is standard deviation of S greater than or less than that of T?
1). Range of S is greater that of T
2). Average of S is greater than that of T
Source: — Data Sufficiency |

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by sam2304 » Thu Jan 12, 2012 3:37 am
Set S and T have 100 numbers, respectively. Is standard deviation of S greater than or less than that of T?
1). Range of S is greater that of T
Range of S is 10, Range of T is 9. We don't know the individual values in each of the sets without which SD cannot be determined. INSUFF
2). Average of S is greater than that of T
SD is distribution of values with mean. Without knowing the values/difference of each number with mean we cannot determine the SD of any set.

Combining together, we get the same, no info about any values in the set and hence INSUFF.
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