AI InterviewSearch…Search problems, topics, or pages…Ctrl KGet started

Topic

Problems on Ages aptitude questions

Relations between ages now, before and after — set up once, solve once.

0 of 33 solved in this view

Formula sheetProblems on Ages: the essentialsFormula sheetProblems on Ages: the essentialsShow

  • The difference between two people's ages never changes, which makes it the fastest check on any answer.
  • Give the present ages one variable. 'n years ago' subtracts n from every age; 'n years hence' adds n.
  • Present ratio a : b, becoming c : d after n years: (ax + n)/(bx + n) = c/d, then cross-multiply. The equation is always linear.
  • If one age is k times the other, their difference is (k − 1) × the younger age.
  • A group's total age rises by the number of people each year, so t years ago it was the present total − people × t.
  • For children born at equal intervals, the sum of their ages = count × the middle child's age (for an odd count).
  • 'I was as old as you are now when you were born' means the parent's age at the birth equals the child's present age, so the parent is now twice as old.
  • Given a product and a difference: (a + b)² = (a − b)² + 4ab.
  • Turn awkward percentages into fractions: 125% = 5/4, 150% = 3/2, 83⅓% = 5/6.
  • Apply a ratio to present ages only; bring a past or future age back to the present first.

Example: a father is four times his son's age and in 16 years will be twice it. 4x + 16 = 2(x + 16) gives x = 8, so the son is 8 and the father 32.

Questions33

1

Father three times the son

A father is three times as old as his son. In 12 years he will be twice as old. How old is the son now?

basics

45s

Easy
2

Ratio 5 : 7 now, 3 : 4 later

The ages of A and B are in the ratio 5 : 7. After 6 years the ratio becomes 3 : 4. What is A's present age?

ratio

60s

Medium
3

Mother and daughter

The sum of the ages of a mother and her daughter is 50. Five years ago the mother was seven times as old as the daughter. How old is the mother now?

years ago

60s

Medium
4

Half the age, ten years ago

Ten years ago, Ram was half as old as Shyam. If their present ages are in the ratio 3 : 4, what is the sum of their present ages?

ratio

60s

Medium
5

Product 48, difference 2

The product of the ages of two sisters is 48 and the difference is 2. What is the sum of their ages?

factors

45s

Easy
6

125% of ten years ago

A man's present age is 125% of his age 10 years ago and 83⅓% of his age 10 years hence. What is his present age?

percent

75s

Hard
7

Three times now, four times then

A father is three times as old as his son. Five years ago he was four times as old. What is the father's present age?

basics

75s

Medium
8

Three times now, twice later

A man is three times as old as his son. Fifteen years hence he will be twice as old. What is the man's present age?

basics

75s

Medium
9

Twice now, three times before

A is twice as old as B. Ten years ago A was three times as old as B. What is B's present age?

basics

75s

Medium
10

Ratio 6 : 5 now, 9 : 8 later

The ages of A and B are in the ratio 6 : 5. After 15 years the ratio becomes 9 : 8. What is A's present age?

ratio

75s

Medium
11

Ratio 3 : 5 now, 3 : 4 later

The ages of A and B are in the ratio 3 : 5. After 9 years the ratio becomes 3 : 4. What is B's present age?

ratio

75s

Medium
12

Looking back eight years

The present ages of two people are in the ratio 3 : 4. Eight years ago they were in the ratio 2 : 3. What is the sum of their present ages?

ratio

75s

Medium
13

One year ago and four years hence

One year ago the ages of two people were in the ratio 5 : 6. Four years hence the ratio will be 6 : 7. What is the present age of the younger?

ratio

120s

Hard
14

Mother and daughter

The sum of the ages of a mother and her daughter is 50. Five years ago the mother was seven times as old as the daughter. What is the mother's present age?

sum

90s

Medium
15

Ages differing by 16

The ages of two people differ by 16 years. Six years ago the elder was three times as old as the younger. What is the younger's present age?

difference

90s

Medium
16

Father thirty years older

A father is 30 years older than his son. In 12 years the father will be three times as old as his son. What is the son's present age?

difference

75s

Medium
17

Twenty years older

A is 20 years older than B. In 5 years A will be twice as old as B. What is B's present age?

difference

60s

Medium
18

Ratio and product together

The ratio of a man's age to his son's is 7 : 3 and the product of their ages is 756. What will the ratio be after 6 years?

ratio · product

105s

Hard
19

Product 48, difference 2

The product of two sisters' ages is 48 and their difference is 2. What is the sum of their ages?

factors

45s

Easy
20

150% of his age eight years ago

A man's present age is 150% of his age 8 years ago. What is his present age?

percentages

75s

Medium
21

Fifteen years hence, five times five back

A man's age after 15 years will be five times his age 5 years ago. What is his present age?

basics

60s

Medium
22

As old as you at your birth

A father tells his son, 'I was as old as you are now at the time of your birth.' If the father is 38 now, what was the son's age five years back?

wordy

90s

Medium
23

Three linked ages

A is two years older than B, who is twice as old as C. If the total of their ages is 27, what is B's age?

three people

90s

Medium
24

Five children, three years apart

The sum of the ages of five children born at intervals of 3 years each is 50 years. What is the age of the youngest?

series

75s

Medium
25

Husband, wife and child

Three years ago the average age of a husband, wife and child was 27. Five years ago the average age of the wife and child was 20.

averages

120s

Hard
26

The family at the youngest's birth

The average age of a family of five is 20 years. The youngest is 5 years old. What was the average age of the family at the birth of the youngest?

averages

135s

Hard
27

Four more than four times

A father's present age is 4 more than four times his son's. After 4 years he will be 2 more than three times his son's age. What is the father's present age?

algebra

120s

Hard
28

From a future age to a present one

The ages of A and B are in the ratio 4 : 3. A will be 26 years old in 6 years. What is B's present age?

ratio

45s

Easy
29

Younger by seven years

Sachin is younger than Rahul by 7 years and their ages are in the ratio 7 : 9. What is Sachin's age?

ratio

60s

Medium
30

Twice as old, five years ago

Five years ago A was twice as old as B. Their present ages are in the ratio 9 : 5. What is A's present age?

ratio

90s

Medium
31

How the sum of ages grows

The sum of the present ages of a father and son is 60 years. Six years ago the father's age was five times the son's. What will the son's age be after 6 years?

sum

120s

Hard
32

A teacher among the students

The average age of a class of 24 students is 16 years. If the teacher's age is included, the average rises by 1 year. What is the teacher's age?

averages

60s

Medium
33

Three times as old, twelve years apart

The ages of two brothers differ by 12 years and the elder is three times as old as the younger. What is the elder brother's age?

difference

45s

Easy

Showing 33 of 33

Problems on Ages Aptitude Questions with Solutions

33 Problems on Ages questions with hints, worked solutions and time targets — 5 easy · 21 medium · 7 hard.

  • Section: Quantitative Aptitude
  • Questions: 33
  • By difficulty: 5 easy · 21 medium · 7 hard
  • Cost: Free, unlimited on every plan

Relations between ages now, before and after — set up once, solve once.

Problems on Ages: the essentials

  • The difference between two people's ages never changes, which makes it the fastest check on any answer.
  • Give the present ages one variable. 'n years ago' subtracts n from every age; 'n years hence' adds n.
  • Present ratio a : b, becoming c : d after n years: (ax + n)/(bx + n) = c/d, then cross-multiply. The equation is always linear.
  • If one age is k times the other, their difference is (k − 1) × the younger age.
  • A group's total age rises by the number of people each year, so t years ago it was the present total − people × t.
  • For children born at equal intervals, the sum of their ages = count × the middle child's age (for an odd count).
  • 'I was as old as you are now when you were born' means the parent's age at the birth equals the child's present age, so the parent is now twice as old.
  • Given a product and a difference: (a + b)² = (a − b)² + 4ab.
  • Turn awkward percentages into fractions: 125% = 5/4, 150% = 3/2, 83⅓% = 5/6.
  • Apply a ratio to present ages only; bring a past or future age back to the present first.

Example: a father is four times his son's age and in 16 years will be twice it. 4x + 16 = 2(x + 16) gives x = 8, so the son is 8 and the father 32.

Questions

  1. Father three times the son Easy
    A father is three times as old as his son. In 12 years he will be twice as old. How old is the son now?
  2. Ratio 5 : 7 now, 3 : 4 later Medium
    The ages of A and B are in the ratio 5 : 7. After 6 years the ratio becomes 3 : 4. What is A's present age?
  3. Mother and daughter Medium
    The sum of the ages of a mother and her daughter is 50. Five years ago the mother was seven times as old as the daughter. How old is the mother now?
  4. Half the age, ten years ago Medium
    Ten years ago, Ram was half as old as Shyam. If their present ages are in the ratio 3 : 4, what is the sum of their present ages?
  5. Product 48, difference 2 Easy
    The product of the ages of two sisters is 48 and the difference is 2. What is the sum of their ages?
  6. 125% of ten years ago Hard
    A man's present age is 125% of his age 10 years ago and 83⅓% of his age 10 years hence. What is his present age?
  7. Three times now, four times then Medium
    A father is three times as old as his son. Five years ago he was four times as old. What is the father's present age?
  8. Three times now, twice later Medium
    A man is three times as old as his son. Fifteen years hence he will be twice as old. What is the man's present age?
  9. Twice now, three times before Medium
    A is twice as old as B. Ten years ago A was three times as old as B. What is B's present age?
  10. Ratio 6 : 5 now, 9 : 8 later Medium
    The ages of A and B are in the ratio 6 : 5. After 15 years the ratio becomes 9 : 8. What is A's present age?
  11. Ratio 3 : 5 now, 3 : 4 later Medium
    The ages of A and B are in the ratio 3 : 5. After 9 years the ratio becomes 3 : 4. What is B's present age?
  12. Looking back eight years Medium
    The present ages of two people are in the ratio 3 : 4. Eight years ago they were in the ratio 2 : 3. What is the sum of their present ages?
  13. One year ago and four years hence Hard
    One year ago the ages of two people were in the ratio 5 : 6. Four years hence the ratio will be 6 : 7. What is the present age of the younger?
  14. Mother and daughter Medium
    The sum of the ages of a mother and her daughter is 50. Five years ago the mother was seven times as old as the daughter. What is the mother's present age?
  15. Ages differing by 16 Medium
    The ages of two people differ by 16 years. Six years ago the elder was three times as old as the younger. What is the younger's present age?
  16. Father thirty years older Medium
    A father is 30 years older than his son. In 12 years the father will be three times as old as his son. What is the son's present age?
  17. Twenty years older Medium
    A is 20 years older than B. In 5 years A will be twice as old as B. What is B's present age?
  18. Ratio and product together Hard
    The ratio of a man's age to his son's is 7 : 3 and the product of their ages is 756. What will the ratio be after 6 years?
  19. Product 48, difference 2 Easy
    The product of two sisters' ages is 48 and their difference is 2. What is the sum of their ages?
  20. 150% of his age eight years ago Medium
    A man's present age is 150% of his age 8 years ago. What is his present age?
  21. Fifteen years hence, five times five back Medium
    A man's age after 15 years will be five times his age 5 years ago. What is his present age?
  22. As old as you at your birth Medium
    A father tells his son, 'I was as old as you are now at the time of your birth.' If the father is 38 now, what was the son's age five years back?
  23. Three linked ages Medium
    A is two years older than B, who is twice as old as C. If the total of their ages is 27, what is B's age?
  24. Five children, three years apart Medium
    The sum of the ages of five children born at intervals of 3 years each is 50 years. What is the age of the youngest?
  25. Husband, wife and child Hard
    Three years ago the average age of a husband, wife and child was 27. Five years ago the average age of the wife and child was 20.
  26. The family at the youngest's birth Hard
    The average age of a family of five is 20 years. The youngest is 5 years old. What was the average age of the family at the birth of the youngest?
  27. Four more than four times Hard
    A father's present age is 4 more than four times his son's. After 4 years he will be 2 more than three times his son's age. What is the father's present age?
  28. From a future age to a present one Easy
    The ages of A and B are in the ratio 4 : 3. A will be 26 years old in 6 years. What is B's present age?
  29. Younger by seven years Medium
    Sachin is younger than Rahul by 7 years and their ages are in the ratio 7 : 9. What is Sachin's age?
  30. Twice as old, five years ago Medium
    Five years ago A was twice as old as B. Their present ages are in the ratio 9 : 5. What is A's present age?
  31. How the sum of ages grows Hard
    The sum of the present ages of a father and son is 60 years. Six years ago the father's age was five times the son's. What will the son's age be after 6 years?
  32. A teacher among the students Medium
    The average age of a class of 24 students is 16 years. If the teacher's age is included, the average rises by 1 year. What is the teacher's age?
  33. Three times as old, twelve years apart Easy
    The ages of two brothers differ by 12 years and the elder is three times as old as the younger. What is the elder brother's age?

Placement tests that ask problems on ages