Quantitative Aptitude

Problems on Ages

348 Questions

Problems on Ages involve calculating current, past, or future ages using ratios, averages, and simple equations. These questions are a regular feature in the arithmetic section of most competitive exams. Practicing these problems helps improve calculation speed and accuracy for time management during tests.

age ratiosaverage age problemspresent age calculationsfuture age equationsfamily age puzzles

Problems on Ages Questions

Multiple choice maths ways to multiply and divide mental multiplication multiplication methods multiplication of numbers

The average age of a family of 6 members 4 years ago was 25 years. Meanwhile a child was born in this family and still the average age of the whole family is same today. The present age of child is ......

  1. 2 years
  2. $1 \displaystyle \frac{1}{2} $ years

  3. 1 years

  4. Data insufficient
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Total age of 6 family members four year ago =$25\times 6=150$years
Total age of 6 family member now=150+$4\times 6=150+24=174$years
Total age of 6 family member and child =$25\times 7=175$year
Age of child =175-174=1 year

Multiple choice

My brother Sammy is three years older than me.

  1. I'm tree years younger than my brother Sammy.

  2. I'm three years youngger than my brother Sammy.

  3. I'm three years younger than my brother Sammy.
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Option C is the correct sentence. It uses the correct comparative 'younger' and the correct spelling.

Multiple choice

How old is earth?

  1. 4.6 years

  2. 4.6 thousand years

  3. 4.6million

  4. 4.6 billion
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Scientific consensus based on radiometric dating of meteorites and Earth rocks places the age of the Earth at approximately 4.6 billion years.

Multiple choice maths ratio, proportion and unitary method converting to ratios finding ratios other quantities

The ratio of the present ages of two brothers is $1:2$ and $5$ years back the ratio was $1:3$. What will be the ratio of their ages after $5$ years?

  1. $1:4$
  2. $2:3$
  3. $3:5$
  4. $5:6$
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Let the age of the two brothers be $x$ and $y$ respectively


Given


At present 

$\dfrac { x }{ y } =\dfrac { 1 }{ 2 } \Rightarrow y=2x$

Five years ago

$\dfrac { x-5 }{ y-5 } =\dfrac { 1 }{ 3 }$

substitute $y=2x$ 

$\dfrac { x-5 }{ 2x-5 } =\dfrac { 1 }{ 3 }$

$\Rightarrow 3x-15=2x-5\Rightarrow x=10$

$\Rightarrow y=2x=2(10)=20$

$\therefore\ x=10$ and $y=20$

Required ratio:

$\displaystyle \frac { x+5 }{ y+5 } =\frac { 10+5 }{ 20+5 } =\frac { 15 }{ 25 } =\frac { 3 }{ 5 }$

Hence option (C) is the correct option.

Multiple choice maths ratio, proportion and unitary method converting to ratios finding ratios other quantities

The ratio between the ages of $A$ and $B$ is $2 : 5$. After $8$ years, their ages will be in the ratio $1 : 2$. What is the difference between their present ages?

  1. $20$ years
  2. $22$ years
  3. $24$ years
  4. $25$ years
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Let $A = 2x; B = 5x$ be the present ages of $A$ and $B$ respectively.
After $8$ years, their ages will be $(2x + 8)$ years and $(5x + 8)$ years respectively.
Therefore, $ (2x + 8) : (5x + 8) : : 1 : 2$
$\Rightarrow  (5x + 8)\times 1 = 2(2x + 8)$
$\Rightarrow x = 8$
Thus difference of their present ages is $5x - 2x = 3x$ i.e., $24$ years.

Multiple choice time speed and distance problems involving speed word problems on speed time and distance time and distance word problems on simultaneous equations applications of simultameous equations unitary method idea of speed distance and time speed math time work and distance ratio and proportions linear equations in two variables maths

The present ages of Reena and Usha ar 24 and 36 yr respectively. What was the ratio between the ages of Usha and Reena respectively 8 yr ago?

  1. 7:4

  2. 4:7

  3. 11:8

  4. 8:11
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Age of Reena after 8yr=24−8=16yr
Age of Usha After 8yr=36−8=28
So, the ratio will be 1628=47

Multiple choice maths average arithmetic mean of ap introduction to averages means

The average age of $30$ girls. is $13\ yr$. The average of first $18$ girls is $15\ yr$. Find out the average age of remaining $12$ girls? 

  1. $12\ yr$
  2. $10\ yr$
  3. $16\ yr$
  4. $10.5\ yr$
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Multiply the total count by the overall average to find the total sum of ages, which is 30 * 13 = 390. Next, find the sum of the ages of the first 18 girls by multiplying 18 * 15 = 270. Subtracting this from the total gives 390 - 270 = 120 for the remaining 12 girls, leading to an average of 120 / 12 = 10 years.

Multiple choice maths average arithmetic mean of ap introduction to averages means

The average age of 36 student in a group is 14 years. When teacher's age is included to it, the average increases by one. What is the teacher's age in years?

  1. 31

  2. 36

  3. 51

  4. Cannot be determined

  5. None of these
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

The total age of 36 students is 36 * 14 = 504. When the teacher is added, there are 37 people and the average becomes 15, giving a total sum of 37 * 15 = 555. The teacher's age is the difference between these two totals, which is 555 - 504 = 51.