Question

80 bulbs are selected at random from a lot and their life time (in hrs) is recorded in the form of a frequency table given below:

Life time (in hours)	300	500	700	900	1100
Frequency	10	12	23	25	10

One bulb is selected at random from the lot. The probability that its life is 1150 hours, is

Options

• `1/80`

• `7/16`

• 0

• 1

Answer 1

0

Explanation:

Total bulb in a lot, n(S) = 80

Number of bulbs whose life time is 1150, n(E) = 0

Probability that its life time is 1150 h = `(n(E))/(n(S)) = 0/80 = 0`

Hence, the probability that its life time is 1150 is 0.