DRDO Multi tasking staff Model paper 7

Let, X be the mean proportional
As we know that, mean proportional = √a × b
Where a and b are outer elements of proportion
0.25 : X = X : 6.25
x2=0.25×6.25
X = 1.25
So, the mean proportional between 0.25 and 6.25 = 1.25 Ans.