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Find the value of ‘n’ if the mean of the set of the numbers 8, 5, n, 10, 15, 21 is given as 11.

  1. 5
  2. 7
  3. 4
  4. 6

Answer (Detailed Solution Below)

Option 2 : 7
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Detailed Solution

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CONCEPT:

The mean (or average) of a number of observations is the sum of the values of all the observations divided by the total number of observations. It is denoted by the symbol  , read as ‘x bar’.

Mean 

CALCULATION:

Given set of number is 8, 5, n, 10, 15, 21.

So 

∴   ⇒ n = 7

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