Question 20
A recent survey found that ages of workers in a factory as follows:
Age(in years)20−2930−3940−4950−5960 and aboveNumber of382786463workers
If a person is selected at random, find the probability that the person is:
(i) 40 years or more.
(ii) Under 40 years.
(iii) Having age from 30 - 39 years.
(iv) Under 60 but over 39 years.
Total number of workers in the factory,
n(S)=38+27+86+46+3=200
(i) Number of persons selected at the age of 40 years or more,
n(E1)=86+46+3=135
∴ Probability that the persons selected at the age of 40 years or more,
P(E1)=n(E1)n(S)=135200=0.675
(ii) Number of persons selected under the age of 40 years,
n(E2)=38+27=65
∴ Probability that the persons selected under the age of 40 years,
P(E1)=n(E2)n(S)=65200=0.325
(iii) Number of persons selected having age from 30 to 39 years,
n(E3)=27
∴ Probability that the persons selected having age from 30 to 39 years,
P(E3)=n(E3)n(S)=27200=0.135
(iv) Number of persons selected having age under 60 nut over 39 years,
n(E4)=86+46=132
∴ Probability that the persons selected having age under 60 but over 39 years,
P(E4)=n(E4)n(S)=132200=0.66