The table given below shows the ages of 75 teachers in a school.
Age (in years) | 18-29 | 30-39 | 40-49 | 50-59 |
No of teachers | 5 | 25 | 35 | 10 |
Note Here 18-29 means from 18 to 29 including both. A teacher from the school is chosen at ramdom. What is the probability that the teacher chosen is
(i) 40 years or more then 40 years old?
(ii) 49 years or less then 49 years old?
(iii) 60 years or more then 60 years old?
Total number of teachers: 75
Number of teachers having age 40 years or more than 40 years old: 45
Number of teachers having age 49 years or less than 40 years old: 65 (5+25+35)
Number of teachers having age 60 years or more than 60 years old: 0
Probability P() = 
(i) Let P(more than 40) be probability of teachers having age 40 years or more than 40 years old
P(more than 40) = 
(ii) Let P(less than 49) of teachers having age 49 years or less than 40 years old
P(less than 49) = 
(iii) Let P(more than 60) be probability 60 years or more then 60 years old
P(more than 60) = 