The mean of 12 observations is 75. If two observations are...

The mean of 12 observations is 75. If two observations are discarded, then the mean of the remaining observations is 65. What is the mean of the discarded observations?

Options

A $250$
B $125$
C $120$
DCannot be determined due to insufficient data

Correct answer

B. $125$

Step-by-step solution

Mean of discarded observation

=\frac{\text{ Sum of } 12 \text{ observation }- \text{ Sum of } 10 \text{ observation }}{2}=\frac{12 \times 75-10 \times 65}{2}=125

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