Aptitude - Problems on Ages - Discussion

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.

@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.

@Khaisar.

The correct answer after solving it was:

(6x+6)+4/(5x+6)+4. = 11/10.
(6x+6)+4.

10(6x+10) = 11(5x+10),
60x+100 = 55x+110,
60x-55x = 110-100,
5x = 10,
x = 10÷2,
x = 5.

Sugar current age = 5x + 6,
= 10+6,
= 16.

Answer=16

Step 1:

Let us consider kunal age is = x and sager age is = y.

Six years ago ages of kunal and sager is = 6:5.

So we can write x-6/y-6 = 6/5--->A.

Next, four years hence ages of kunal and sager is = 11:10.

So we can write x+4/y+4 = 11/10--->B.

Step-2:

Solve equation A and B, so.

Eqn A becomes,

X-6/y-6 = 6/5, so cross multiply becomes.

5x-30 = 6y-36->5x-6y+6 = 0.

5x-6y = -6-->C.

Eqn B becomes,

X+4/y+4 = 11/10, so cross multiply becomes.

10x+40 = 11y+44-->10x-11y-4 = 0.

10x-11y = 4-->D.

Solve eqn C and D.

5x-6y = -6->C.

10x-11y = 4->D.

2xeqn c, we get.

10x-12y = -12->E.

10x-11y = 4->D.

Step 3:

Eqn E (-) eqn D, so we can get.

10x-12y = -12.

-10+11y = -4.

So -y = -16.

We know (-) is cancel, so y = 16 = sager age.

Really I feel my explanation will under stand you.

My answer will be simple and easy.chexh this out:

6 years ago the ratio is 6x/5x(since a/b so we should take it as ax/bx).
Now the present ages are 6x+6/5x+6(since 6x/5x are the ages 6 years before),
After four years to the present age so (6x+6)+4/(5x+6)+4 = 11/10,
60x+100 = 55x+110,
5x = 10,
X = 2.

Since the present age of the second guy is 5x+6.
5(2)+6.
=16(final answer).

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.

6:5 =>6/5:1.
Its means kunam 6/5 times of Sagar's age
4 year later =>11/10:1.
Put into formula= (6(6/5-1)+4(11/10-1))/6/5-11/10.
= 16.

Why we have added 6 years instead of deducting as it is given that 6 years ago?

What is the differece between "ago" and "hence" if at the both times 6 was added?

Is it sumthing like 6x-(-6)????