UPSC Prelims 2001 Q143: Science & Technology – Quantitative Aptitude
A city has a population of 3,00,000 out of which 1,80,000 are males. 50% of the population is
literate. If 70% of the males are literate, the number of literate females is
- (a) 24,000
- (b) 30,000
- (c) 54,000
- (d) 60,000
Answer: (a) 24,000
Explanation
Number of literate females in the city
| Item | Working |
|---|---|
| Total literate (50%) | 50% of 3,00,000 = 1,50,000 |
| Literate males (70% of 1,80,000) | 1,26,000 |
| Literate females | 1,50,000 − 1,26,000 = 24,000 |
| Females in all | 3,00,000 − 1,80,000 = 1,20,000 (so female literacy = 20%) |
Given: a city population of 3,00,000 with 1,80,000 males; 50% of the population and 70% of the males are literate. Literate people number 1,50,000 and literate males 1,26,000, so literate females = 24,000.
Answer: (a) 24,000.
Why each option is right or wrong
- (a) CORRECT. 1,50,000 − 1,26,000 = 24,000.
- (b) Incorrect. 30,000 does not match the given figures.
- (c) Incorrect. 54,000 is not the difference.
- (d) Incorrect. 60,000 would be half of all females.
Key point
Census 2011: literacy 74%; male 82%, female 65%.
Remember
1,50,000 − 1,26,000 = 24,000 literate females.
Common mistakes
- Taking 50% of females instead of the whole population.
- Taking 70% of the whole population for males.
- Subtracting from the female total instead.
Exam tip
Total literate − male literate = female literate.
Sources
- NCERT Class VIII — Mathematics, chapters 'Comparing Quantities' and 'Direct and Inverse Proportions'
- R. S. Aggarwal — Quantitative Aptitude, chapter 'Percentage'