Question

Assuming a normal distribution, if P(x<2)= 0.4 and P(x<4) = 0.6, which of the following is FALSE?

A	P(x<6) = 1
B	P(2<x<4) =0.2
C	P(x>=4) = 1-P(x<4)
D	Mean = 3

Answer 1

Consider option C:

which is true because it's a basic principle.

Consider option D:

From C,

Hence, the normal distribution is symmetrical about x = 3

We know that, normal distribution is symmetrical about it's mean.

Hence, from this knowledge, Mean = 3

Therefore, option D is true.

Consider option B:

Hence, option B is true

By method of elimination we can say that Option A is False.