<PRE><B>Question 815463</B>
The average age of a group went up by 2 years when a man aged 34 years was replaced by an old man aged 58 years
 How many members were there in the group?
:
Let n = number of men in the group, assume they are all 34 yrs old
:
{{{((34(n-1)+58))/n}}} = 34 + 2
34(n-1) + 58 = 36n
34n - 34 + 58 = 36n
24 = 36n - 32n
24 = 2n
n = 12 members in the group
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