Question

Following are the ages (in years) of 300 patients,
getting medical treatment in a hospital:
Age (in years)
Number of patients
10-20
90
20-30
45
30-40
65
40-50
80
50-60
50
60-70
30
One of the patients is selected at random.
Find the probability that his age is:
(1) 10 years or more
(ii) less than 10 years
(i) 30 years or more but less than 40 years
(iv) 50 years or more but less than 70
years.​

Answer 1

P(E)= Number of favourable outcomes/ Total number of outcomes

i) 90/300 = 9/30 = 3/10

ii) 0

iii) 65/300= 13/60

iv) 50+30= 80

Probability= 80/300= 8/30 = 4/15