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 5 of 6.
Khush sharma said:
9 years ago
Let mother's age = 5x,
So person's age will be 2/5 * 5x = 2x,
So the ratio of son and mother will be = 2x : 5x,
Note: One-half means only half and one and half mean 3/2.
After 8 years:
(2x + 8) = 1/2 * (5x + 8),
2(2x + 8) = (5x + 8),
4x + 16 = 5x + 8,
x = 8.
Now mother's present age = 5 * 8 = 40.
So person's age will be 2/5 * 5x = 2x,
So the ratio of son and mother will be = 2x : 5x,
Note: One-half means only half and one and half mean 3/2.
After 8 years:
(2x + 8) = 1/2 * (5x + 8),
2(2x + 8) = (5x + 8),
4x + 16 = 5x + 8,
x = 8.
Now mother's present age = 5 * 8 = 40.
(1)
Ali arif said:
9 years ago
After 8 years, the age of the mother is 40 years.
Pabitra gogoi said:
9 years ago
Your solution is the best, Thanks @Yuga.
Manoj said:
8 years ago
What is the age difference between mother and person?
Jyothi chauhan said:
8 years ago
Hey guys.
Can I know how is that 5 (x+8) has written, Anyone please explain me?
Can I know how is that 5 (x+8) has written, Anyone please explain me?
(1)
Harihara said:
7 years ago
32 will be the answer. In all the solutions 8 is added to find the age. So definitely 40 is not the answer.
Gaurav said:
7 years ago
40 is the age of mother after 8 years. So we must subtract 8 from it.
Priyanka said:
7 years ago
We can solve it in ratio method,
Present age=P : M =2:5
Age after 8 yrs=P(8):M(8)=1:2,
To equalise the difference we multiply both the numbers with there differences=2:5*1,1:2*3
We get, 2:5
3:6
The difference of both the numbers is equal that is 1.
1=8,
5=8*5 = 40yrs,
Mother's age is 40 yrs.
Present age=P : M =2:5
Age after 8 yrs=P(8):M(8)=1:2,
To equalise the difference we multiply both the numbers with there differences=2:5*1,1:2*3
We get, 2:5
3:6
The difference of both the numbers is equal that is 1.
1=8,
5=8*5 = 40yrs,
Mother's age is 40 yrs.
(1)
Prasanna said:
7 years ago
Question says one-half of the age, Not one and half.
So,It's 1/2 not 3/2.
So,It's 1/2 not 3/2.
(2)
Karthika said:
7 years ago
Thanks @Yuga.
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