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Statistics question

2021 · 25 Jul · Shift 2 · Q25
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  5. /2021 · 25 Jul · Shift 2 · Q25

Statistics question

2021 · 25 Jul · Shift 2 · Q25

JEE MainMathematicsStatisticsMCQ+4 / −1
The first of the two samples in a group has 100 items with mean 15 and standard deviation 3. If the whole group has 250 items with mean 15.6 and standard deviation 13.44\sqrt {13.44}13.44​, then the standard deviation of the second sample is :
  1. A
    8
  2. B
    6
  3. C
    4
  4. D
    5
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