Q49Multiple choice
Let X be a discrete random variable whose probability distribution is defined as follows: k ( x + 1) for x = 1, 2,3, 4 P (X = x) = 2kx for x = 5,6,7 0 otherwise 278 MATHEMATICS where k is a constant. Calculate
- (i)the value of k
- (ii)E (X)
- (iii)Standard deviation of X.