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**axa121** Hi could anyone check if I have done the following questions correctly and also help me out with a couple:

The random variable X has N(2,3) distribution. Evaluate:

(i) P( X > 3 )

(ii) P(-1 < X < 4 )

(iii) Find a, such that P( (X-2) < a ) = 0.1

So for part (i) I have P(Z> (1/root3) )

and for part (ii) i have P( Z < (2/root3) - P (Z < -3/root3) Mr F says: Once you have the z-values you should have been taught how to use standard normal tables to get the required probabilities (look in your classnotes or textbook).

Second question is:

The random variables X and Y are independent N(1,5) and N(5,1).

Evaluate:

(i) P( X < 0, Y > 6) and

(ii) P ( -3 < 3X - Y < 0)

Thanks.