Question

A fair coin is tossed 99 times. If X is the number of times head occurs, P(X = r) is maximum when r is ______.

विकल्प

• 49 or 50

• 50 or 51

• 51

• None of these

Answer 1

A fair coin is tossed 99 times. If X is the number of times head occurs, P(X = r) is maximum when r is 49 or 50.

Explanation:

Putting n = 99 and p = `1/2`,

we have (n + 1)p

= `(100)(1/2)`

= 50

so that the maximum value of P(X = r) occurs at r

= (n + 1)p = 50 and at r = (n + 1)p – 1 = 49