If range is less than 9, then the difference between the largest and teh smallest members of the set should be ,9
The difference of all the given numbers < 9
So even if we were to assume that the difference between x and y is less than 18
then let us try to find values of x and y
So x = 7 + 10 = 17
y can be the same as well = 7 + 10 = 17
So x + y can be > 18,
Again, x+y can be any other numbers as 1 and 2, and the range is still < 9.
so (1) is not sufficient.
(x+y)/2 < (7 + y + 12 + 8 + x + 9)/6
=> 6(x+y) < 2(x+y + 36)
=> 4(x+y) < 2*36
=> (x+y) < 18
So Answer - B
Formula of Life -> Achievement/Potential = k * Happiness (where k is a constant)
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