Age Riddles With Answers
Updated · Best Riddles With Answers editorial team
Quick answer: This page has 42 age riddles with answers, built around birthdays, family ages, twins and the years that pass. It suits students, parents and puzzle fans who like a little algebra without the fuss. Each answer shows the working in a clause, so you can check the sums yourself. Begin with the easy riddles and work up to the hard ones.
Easy Age Riddles
Tom is 8 years old. His sister is 3 years older. How old is she?
11, because 8 + 3 = 11.
I am 10 years old now. How old will I be in 5 years?
15, because 10 + 5 = 15.
Mum is 30 years older than her daughter, who is 7. How old is Mum?
37, because 7 + 30 = 37.
Grandpa is 70 and his grandson is 10. How many times older is Grandpa?
7 times, because 70 / 10 = 7.
Ann was 6 years old four years ago. How old is she now?
10, because 6 + 4 = 10.
One of a pair of twins is 9 years old. How old is the other twin?
9, because twins are born together.
Ben is 12 and his brother is half his age. How old is the brother?
6, because 12 / 2 = 6.
A baby is 24 months old. How many years old is she?
2, because 24 / 12 = 2.
Lee is 9 and Sam is 5 years older than Lee. What do their ages add up to?
23. Sam is 9 + 5 = 14, and 9 + 14 = 23.
Dad is 40 and his son is 10. How old was Dad when his son was born?
30, because 40 - 10 = 30.
In 3 years I will be 11. How old am I now?
8, because 11 - 3 = 8.
You are 2 years older than your cousin. How much older will you be than your cousin in 10 years?
2 years. The gap between two ages never changes.
Trickier Age Riddles
Sue is twice as old as Ben, who is 6. How old will Sue be when Ben is 10?
16. Sue is 12 now, Ben needs 4 more years, and 12 + 4 = 16.
A mother is 3 times as old as her son, and their ages add up to 48. How old is each?
Son 12, mother 36, because 12 + 36 = 48 and 12 x 3 = 36.
Dad is 35 and his son is 5. In how many years will Dad be exactly 3 times as old as his son?
10 years. Then Dad is 45 and the son is 15, and 15 x 3 = 45.
Two sisters' ages add up to 20 and they are 4 years apart. How old are they?
12 and 8. 12 + 8 = 20 and 12 - 8 = 4.
Jack is 4 years younger than Jill. Jill is 3 years older than Kim, who is 10. How old is Jack?
9. Jill is 10 + 3 = 13, and Jack is 13 - 4 = 9.
Three brothers have consecutive ages that add up to 36. How old are they?
11, 12 and 13. The middle age is 36 / 3 = 12.
In 5 years Tom will be twice as old as he was 5 years ago. How old is he now?
15. In 5 years he is 20, 5 years ago he was 10, and 20 = 2 x 10.
Mia is 4 times as old as her little brother. In 2 years she will be 3 times as old as him. How old are they now?
Mia 16, brother 4. In 2 years they are 18 and 6, and 18 = 3 x 6.
A father is 4 times as old as his son. In 20 years he will be twice as old. How old are they now?
Father 40, son 10. In 20 years they are 60 and 30, and 60 = 2 x 30.
Half my age plus 5 equals my age minus 5. How old am I?
20. Half of 20 is 10, 10 + 5 = 15, and 20 - 5 = 15.
Gran is 66, which is 6 times her granddaughter's age. How old is the granddaughter?
11, because 66 / 6 = 11.
A man is 5 years older than his wife, and their ages add up to 75. How old are they?
Man 40, wife 35, because 40 + 35 = 75 and 40 - 35 = 5.
Hard Age Riddles
Ten years ago a father was 3 times as old as his son. In 10 years he will be twice as old. How old are they now?
Father 70, son 30. Ten years ago 60 and 20; in 10 years 80 and 40, and 80 = 2 x 40.
I am twice as old as you were when I was as old as you are now. Together we are 63. How old are we?
I am 36 and you are 27. Nine years ago I was 27 and you were 18, and 36 = 2 x 18.
A mother is 21 years older than her child. In 6 years she will be 5 times as old as the child. How old is the child now?
Minus 9 months: the child is not born yet. Child + 27 = 5 x (child + 6) gives child = -3/4 of a year.
A father is 3 times as old as his son. In 15 years he will be twice as old. How old are they now?
Father 45, son 15. In 15 years they are 60 and 30, and 60 = 2 x 30.
The ages of three children multiply to 36 and add up to 13. There is one oldest child. How old is each child?
2, 2 and 9. Both 1, 6, 6 and 2, 2, 9 add to 13, but only 2, 2, 9 has one oldest child.
Tom is 3 years older than Ann, and Ann is 2 years older than Bo. Their ages add up to 40. How old is each?
Bo 11, Ann 13, Tom 16, because 11 + 13 + 16 = 40.
In 4 years Lena will be twice as old as Ria. Four years ago she was 4 times as old. How old are they now?
Lena 20, Ria 8. In 4 years: 24 and 12. Four years ago: 16 and 4.
I am between 20 and 50, and my age is a multiple of both 5 and 7. How old am I?
35, because 5 x 7 = 35 and the next multiple, 70, is too high.
A woman born on 29 February has had exactly 5 birthdays on that date. How old can she be?
Between 20 and 23. Her real birthdays came at ages 4, 8, 12, 16 and 20, and the next is at 24.
Two people have the same mother, the same birthday and the same birth year, but they are not twins. How?
They are two of triplets (or more).
Quick-Fire Age Riddles
It goes up every birthday and never comes down.
Age.
You blow them out and make a wish.
Candles.
Someone who has reached one hundred years.
Centenarian.
A person aged between thirteen and nineteen.
Teenager.
Ten years.
Decade.
One hundred years.
Century.
Three babies born to one mother on the same day.
Triplets.
A very young baby.
Infant.
How to Use These Riddles
Age riddles are algebra in disguise. Give the unknown age a letter, write each clue as a small sum, and check your answer by putting the ages back into every clue. The gap between two people's ages never changes, which is the key to many of them.
For younger children, use the easy section with real family members. For older students, the hard section is good practice for forming and solving equations, and every answer shows a check you can copy.
Frequently Asked Questions
How do you solve an age riddle?
Let one person's age be x, write the other ages in terms of x, and turn each clue into an equation. Solve for x, then check the answer against every clue in the riddle.
Why does the age gap between two people stay the same?
Both people get one year older each year, so the difference never changes. This fact solves many age riddles, because the gap is known at any moment in time.
What is the answer to the riddle about three children with ages that multiply to 36?
The ages are 2, 2 and 9. Two sets of ages multiply to 36 and add to 13, which are 1, 6, 6 and 2, 2, 9, and only the second has a single oldest child.
Are these age riddles suitable for children?
Yes. The easy section uses simple adding and subtracting with small numbers, and the later sections add multiplication and equations that suit older children and adults.
