Hi Vishnu, In all cases the mean of set of numbers is equal to (Sum of all observations/ Total number of observations). Middle number, if the number of terms is even Find (n/2)th and ((n/2) + 1)th term The average of (n/2)th and ((n/2) + 1)th term will give you the middle term.
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What if the terms are in AP or GP but the no. of terms are even, How will we compute the Mean then? What would be the middle number ?
Hi Vishnu,
In all cases the mean of set of numbers is equal to (Sum of all observations/ Total number of observations).
Middle number, if the number of terms is even
Find (n/2)th and ((n/2) + 1)th term
The average of (n/2)th and ((n/2) + 1)th term will give you the middle term.
By distribution curve, 68 % of 9 observations will fall under m + d and m - d. Will this approach yield correct results?
Request you to not complicate and use the above method for getting to the answer quickly! Best wishes for your GMAT!
That formula works only for Normal Distribution. Baskar should not have given a rude reply.