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Mean of 10 numbers is 8. If a new value 30 is added, new mean:
A12
B9
C10
D(80 + 30)/11 = 10
Answer & Solution
Correct answer: D. (80 + 30)/11 = 10
Sum of 10 = 80. After adding 30, sum = 110, count = 11. New mean = 110/11 = 10.
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