Var (x)=2,if u=5x+2,then var (u) is equal to ? ?
i know its 50. but how to reach the final answer

Var(U)=50

Step-by-step explanation:

Given

Var(X) = 2

We have to find

Var(U) when U = 5x+2

So,

When a variable is multiplied with an integer, the variance of that variable is multiplied with the square of that number i.e. Var(aX) = a^2 Var(X) This the property of variance.

As here x is multiplied with 5,

Var(5x) = 5^2 var(X) = 25*2 = 50

If the same integer is added to all the data values, there is no change in variance that is why the +2 will not affect the variance of U ..