Question

Bulbs are packed in cartons each containing 40
bulbs. Seven hundred cartons were
examined for defective bulbs and the results are
given in the following table:
more
Number
of
defective 0 1 2 3 4 5 6 than
bulbs
6
N
2
Frequency 400 180 48 41 18 8 3
One carton was selected at random. What is the
probability that it has
(1) No defective bulb?
(ii) Defective bulbs from 2 to 6 ?
(ii) Defective bulbs less than 4 ?

Answer 1

Step-by-step explanation:

Total number of cartons, n(S) = 700

(i) Number of cartons which has no defective bulb, n(E1)=400

∴ Probability that no defective bulb =n(E1)n(S)=400700=47.

Hence, the probability that no defective bulb is 47

(ii) Number of cartons which has  defective bulbs from 2 to 6, 

n(E2)=48+41+18+8+3=118

∴  Probability that the defective bulb from 2 to 6 =n(E2)n(S)=118700=59350

Hence, the probability that the defective bulb from 2 to 6 is 59350.

(iii) Number of cartons which has defective bulb less than 4,

n(E3)=400+180+48+41=669.

∴ The Probability that the defective bulbs less than 4 =n(E2)n(S)=669700

Hence, the probability that the defective bulb less than 4 is 669700.