Solution:Let the total number of people be x
According to the question
Number of graduates = (1/2) x
Number of post graduates = (1/5) x
Number of double graduates = x − (1/2)x − (1/5)x
= (3/10)x
Number of graduates who are unemployed
= (1/4) × (1/2)x = (1/8)x
Number of post graduates who are unemployed
= (3/5) × (1/5)x = (3/25)x
Number of double double graduates who are unemployed
= (1/2) (1/10)x = (3/20)x
Total number of people who are employed
= x − (3/8)x − (3/25)x − (3/20)x = (71/200)x
The percentage of people who are employed
= (71x/200) × 100 = 35.5%