Aptitude - Problems on Ages - Discussion
Discussion Forum : Problems on Ages - General Questions (Q.No. 13)
                   
                                       
                                13.
A person's present age is two-fifth of the age of his mother. After 8 years, he will be one-half of the age of his mother. How old is the mother at present?
 
                                    Answer: Option
                                                    Explanation:
                                                Let the mother's present age be x years.
| Then, the person's present age = | ![]()  | 
    2 | x | ![]()  | 
    years. | 
| 5 | 
![]()  | 
    ![]()  | 
    2 | x + 8 | ![]()  | 
    = | 1 | (x + 8) | 
| 5 | 2 | 
 2(2x + 40) = 5(x + 8)
 x = 40.
Discussion:
59 comments Page 1 of 6.
                
                        Prachi said: 
                         
                        1 decade ago
                
                One-half means 3/2 na?
                
                        Jaz said: 
                         
                        1 decade ago
                
                One-half meaning is 1/2 only.
                
                        Aditya said: 
                         
                        1 decade ago
                
                Hey can any one explain properly?
                
                        Yuga J. said: 
                         
                        1 decade ago
                
                @Aditya Ive solved it this way....
The ratio of the person's and his mother's present age is 2:5.
Therefore, take the person's age as 2x and his mother's age as 5x.
After 8 years[(add 8 to both values)...i.e. (2x+8) and (5x+8)] their age ratio is 1:2.
Hence,
(2x+8)/(5x+8)=1/2
4x+16=5x+8
x=8
So, the mother's age=5*8=40
                The ratio of the person's and his mother's present age is 2:5.
Therefore, take the person's age as 2x and his mother's age as 5x.
After 8 years[(add 8 to both values)...i.e. (2x+8) and (5x+8)] their age ratio is 1:2.
Hence,
(2x+8)/(5x+8)=1/2
4x+16=5x+8
x=8
So, the mother's age=5*8=40
                     (10)
                
            
                        Bharathi.m said: 
                         
                        1 decade ago
                
                Thanks yuga.
                
                        Mithu Sen said: 
                         
                        1 decade ago
                
                Hey Yuga.
Thanks your way of explaination was very simple.
                Thanks your way of explaination was very simple.
                        Mrs pallavi said: 
                         
                        1 decade ago
                
                Let the person age x, mother age y.
x=2/5*y............condn(1)
(x+8)=1/2(y+8).....condn(2)
from 1
5x-2y=0.........(a)
from 2
2x-y=-8 ..........(b)
from a & b
we get x=16 & y=40
Answer is 40.
                x=2/5*y............condn(1)
(x+8)=1/2(y+8).....condn(2)
from 1
5x-2y=0.........(a)
from 2
2x-y=-8 ..........(b)
from a & b
we get x=16 & y=40
Answer is 40.
                        Subru said: 
                         
                        1 decade ago
                
                x=mother's age
sons age=2/5*x
x=40(answer)
sons age=100
how this possible
                sons age=2/5*x
x=40(answer)
sons age=100
how this possible
                        Ajith said: 
                         
                        1 decade ago
                
                Good yuga! simplified!
                
                        Deepa said: 
                         
                        1 decade ago
                
                Gr8 Yuga!
Can somebody explain the Actual calculation presented by them?
                Can somebody explain the Actual calculation presented by them?
Post your comments here:
 
            
        Quick links
                            Quantitative Aptitude
                                    
                                    Verbal (English)
                                    
                                    Reasoning
                                    
                                Programming
                                    
                                    Interview
                                    
                                     Placement Papers
                                    
                                

