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The average of 6 numbers is 8. If the number 12 is removed, the average of the remaining 5 is:
A7
B7.5
C7.2
D8
Answer & Solution
Correct answer: C. 7.2
1. Find the total of all six: 8 x 6 = 48.
2. Removing 12 leaves a total of 48 - 12 = 36.
3. Five numbers remain.
4. So the new average is 36 / 5 = 7.2.
5. The average falls because the removed number, 12, was above the old average of 8.
_Source: NCERT Class 10 Maths, Ch 13 'Statistics', S13.2 Mean of Grouped Data_
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