Aptitude - Problems on Ages - Discussion
Discussion Forum : Problems on Ages - General Questions (Q.No. 7)
7.
Six years ago, the ratio of the ages of Kunal and Sagar was 6 : 5. Four years hence, the ratio of their ages will be 11 : 10. What is Sagar's age at present?
Answer: Option
Explanation:
Let the ages of Kunal and Sagar 6 years ago be 6x and 5x years respectively.
| Then, | (6x + 6) + 4 | = | 11 |
| (5x + 6) + 4 | 10 |
10(6x + 10) = 11(5x + 10)
5x = 10
x = 2.
Sagar's present age = (5x + 6) = 16 years.
Discussion:
128 comments Page 2 of 13.
Koknalthang said:
5 years ago
Sir.
Why 5x+6? Why not 5x+4 or 5x-4? Please, anyone, explain.
Why 5x+6? Why not 5x+4 or 5x-4? Please, anyone, explain.
(7)
Jashobanta Nayak said:
5 years ago
Here 'ago' is only mentioned for "hence", so 6 will be added.
Sangay Wangchuk said:
5 years ago
@Swanali.
6 is added because it clearly says that six years ago their age was 6:5. And we are asked to find present ages so we have to add 6 on their age.
6 is added because it clearly says that six years ago their age was 6:5. And we are asked to find present ages so we have to add 6 on their age.
(2)
Swanali lakahane said:
5 years ago
I don't know why 6 is added here, because here it is given ago.
So, please tell me, anyone.
So, please tell me, anyone.
Sreekanth said:
5 years ago
No @Faruk.
He takes six year ago as 6x.
If we take present age as x=5.
Then six years ago in 6x we assign x=5 and it becomes 30.
How it will be right?
He takes six year ago as 6x.
If we take present age as x=5.
Then six years ago in 6x we assign x=5 and it becomes 30.
How it will be right?
Rohini said:
5 years ago
Thank you @Faruk.
Pallavi said:
5 years ago
@All.
By using the Ratio method:
K S (yrs)
6 : 5 ( -6).. 6 yrs ago so minus.
11 : 10 (+4)... After 4 yrs so add 4.
5 ratio = 10... The vertical difference between both the ratio is 5 i.e equal to the sum of the year (add yrs even if signs are different).
So, 1ratio = 2.
Then 2 * 5= 10 ... Sagar ratio is 5.
10+6= 16 yrs --- Add 6 for present age.
By using the Ratio method:
K S (yrs)
6 : 5 ( -6).. 6 yrs ago so minus.
11 : 10 (+4)... After 4 yrs so add 4.
5 ratio = 10... The vertical difference between both the ratio is 5 i.e equal to the sum of the year (add yrs even if signs are different).
So, 1ratio = 2.
Then 2 * 5= 10 ... Sagar ratio is 5.
10+6= 16 yrs --- Add 6 for present age.
Mit Patel said:
5 years ago
Present ages of Kunal is x and sagar is y.
Six years ago,
X-6/y-6=6/5.
After solving this equation I get,
5x-6y=-6.
And 4 year hence,
X-2/y-2=11/10.
After solving this equation I get,
10x-11y=-2.
Now solving this two-equation.
Sagar age is 10 year at present.
Six years ago,
X-6/y-6=6/5.
After solving this equation I get,
5x-6y=-6.
And 4 year hence,
X-2/y-2=11/10.
After solving this equation I get,
10x-11y=-2.
Now solving this two-equation.
Sagar age is 10 year at present.
(1)
Mauni said:
5 years ago
Best solution, Thanks @Amrita.
Amrita rath said:
6 years ago
Let Kunal age be 'x' and Sagar age be 'y'.
6 years ago,
Kunal age is (x-6) years and Sagar age is (y-6) years and their ratio will be 6/5 (given).
x-6/y-6 =6/5 --eq 1.
According to second statement,
x+4/y+4 = 11/10 --eq 2.
Solving these two equations:
5x-30=6y-36 (eq3) and 10x+40=11y+44 (eq 4).
Solving eq 3 and 4 as.
10x+40=11y+44.
-2 (5x-30=6y-36).
------------------------.
10x+40=11y+44.
-10x+60=-12y+72.
------------------------.
100= -y+116.
y= 16 years.
6 years ago,
Kunal age is (x-6) years and Sagar age is (y-6) years and their ratio will be 6/5 (given).
x-6/y-6 =6/5 --eq 1.
According to second statement,
x+4/y+4 = 11/10 --eq 2.
Solving these two equations:
5x-30=6y-36 (eq3) and 10x+40=11y+44 (eq 4).
Solving eq 3 and 4 as.
10x+40=11y+44.
-2 (5x-30=6y-36).
------------------------.
10x+40=11y+44.
-10x+60=-12y+72.
------------------------.
100= -y+116.
y= 16 years.
(2)
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