Practice Questions
Concept Explanation
Age DS problems test whether present or past/future ages can be determined from ratios and time shifts.
Standard Answer Choices
- A — Statement I alone is sufficient; Statement II alone is not.
- B — Statement II alone is sufficient; Statement I alone is not.
- C — Both together are sufficient, neither alone.
- D — Either statement alone is sufficient.
- E — Neither alone nor together is sufficient.
Age DS Focus
Translate “n years ago/later” into equations. Age ratios change over time unless you fix the time gap.
Common Traps in Age Problems
- Applying the same ratio at different time points.
- Forgetting that age difference stays constant.
- Missing integer constraints for present ages.
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Q1 Easy
Father 40, son 10. Ratio of their ages is:
Explanation40 : 10 = 4 : 1. -
Q2 Medium
Present ages 24 and 36. After 6 years ratio will be:
Explanation30 : 42 = 5 : 7. -
Q3 Easy
A is twice as old as B. If B is 15, A is:
ExplanationA = 2 × 15 = 30. -
Q4 Medium
For “Present age of A?” — I: A is 5 years older than B; II: sum of ages is 45. DS answer?
ExplanationA = B + 5 and A + B = 45 ⇒ A = 25. Need both. -
Q5 Medium
Five years ago, ratio of ages was 3 : 5. If present ages are 18 and 30, was that ratio correct?
Explanation5 years ago: 13 and 25, ratio 13 : 25, not 3 : 5. -
Q6 Medium
Sum of ages of two siblings is 50; elder is 6 years older. Younger age is:
Explanationy + (y+6) = 50 ⇒ y = 22. -
Q7 Easy
Father was 30 when son was born. After 12 years, father’s age is:
Explanation30 + 12 = 42.
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Q8 Easy
For “Age difference?” — I: A is 28, B is 19; II: A was 18 when B was 9. DS answer?
ExplanationEach gives difference 9 years. -
Q9 Hard
Ten years hence, A will be twice B. If B is now 20, A is now:
ExplanationA+10 = 2(20+10) ⇒ A = 50. -
Q10 Medium
Ratio of ages 4 : 7; sum is 55. Older person is:
Explanation11 parts = 55; older = 7 × 5 = 35. -
Q11 Medium
For “Present age of father?” — I: father is 3 times son; II: sum is 48. DS answer?
ExplanationF = 3S, F + S = 48 ⇒ F = 36. Need both. -
Q12 Hard
Three years ago mother was 3 times daughter. If mother is now 39, daughter now is:
Explanation3 yrs ago: 36 and 12; now daughter = 15. -
Q13 Easy
Average age of 3 persons 20, 24, 28 is:
Explanation72/3 = 24. -
Q14 Easy
For “Is A older than 30?” — I: A = 35; II: B = 25 and A is 10 years older. DS answer?
ExplanationEach alone confirms A = 35 > 30.
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DS1 Easy
What is the present age of A?
Statement IA is 5 years older than B.
Statement IIThe sum of their present ages is 45.
ExplanationA = B + 5 and A + B = 45 ⇒ A = 25. Need both. -
DS2 Medium
What is the present age of the father?
Statement IThe father is 3 times as old as his son.
Statement IIThe sum of their present ages is 48.
ExplanationF = 3S and F + S = 48 ⇒ F = 36. Need both.
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DS3 Easy
What is the age difference between A and B?
Statement IA is 28 years old and B is 19 years old.
Statement IITen years ago, A was 18 and B was 9.
ExplanationEach statement alone gives difference = 9 years. -
DS4 Easy
How old will A be 5 years from now?
Statement IA is presently 30 years old.
Statement IIB is 25 and A is 5 years older than B.
ExplanationPresent age of A = 30 from either statement; future age = 35.