Question

A group of 20 items have arithmetic mean 5.If the arithmetic mean of 8 of them is 8,then the arithmetic mean of the remaining items is
(a)8. (b)3. (c)5. (d)none of these​

Answer 1

Step-by-step explanation:

3

We know the rule

as D1 + D2 + d3

So

if the first Number is 5 then other is 8 then the other should be 11 as per arithmetic mean

But the difference calculated is 3 too

So according to me the mean is 3