09/08/2024
QUESTION :
If the mean of 7 numbers is 96. Another number was added to make it 8 and the mean is 112. What number was added?
SOLUTION :
Let the sum of 7 numbers whose mean is equal to 96 be S,
Mean= sum of all items/number of items
I.e 96 =S/7
Therefore, S= 7*96
S=672.
Another number is added ( X) and new mean is 112
112= (S+X)/8
112 = (672+X)/8
Cross multiply
672+X = 112*8
672 +X =896
X =896 - 672
X =224.
The number added was 224
