Aptitude - Problems on Ages - Discussion

Discussion Forum : Problems on Ages - General Questions (Q.No. 4)
4.
A is two years older than B who is twice as old as C. If the total of the ages of A, B and C be 27, then how old is B?
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Answer: Option
Explanation:

Let C's age be x years. Then, B's age = 2x years. A's age = (2x + 2) years.

(2x + 2) + 2x + x = 27

5x = 25

x = 5.

Hence, B's age = 2x = 10 years.

Discussion:
79 comments Page 1 of 8.

Dharumaraj S said:   2 decades ago
(b-2)+ b + .5b =27

which is an alternate method to solve the same problem.....

Suresh said:   2 decades ago
Mr Dharumaraj shall you please explain ur answer?
(1)

Shan said:   1 decade ago
Hi,

let c year is x
then B is twice of C then, B=2x
Then A is 2 years older then B, therefore now B=2x,Then A=2+B, that is A=2+2x
Therefore sum up all the value:[(2+2x)for A,2x for B,x for C]
therefore 2+2x+2x+x=27
5x+2=27
5x=27-2
5x=25
x=25/5
x=5
now B is directly linked with C rather then A
Therefore B=2x
where x=5
2*5=10 that'z it my frnd
(2)

Sri said:   1 decade ago
B is twice as old as C means C=2B right?

Raheem said:   1 decade ago
Who is twice as old as c means?

Sweta said:   1 decade ago
We can also solve as
A's age be x yrs. then B's age is x-2 and C's age is(x-2)/2.

Prashanth said:   1 decade ago
Your thought is right but answer will be wrong..just watch
A+B+C=27
x+x-2+(x-2)/2 = 27
2x+2x-4+x-2 = 27*2= 54
5x-6 = 54
5x= 48
Finally x=48/5
which is a wrong ans
always we have to equal the x to the smallest number as per the problem....

SHALINI said:   1 decade ago
I got ur explantion but in solving y cannt we take

2(2x)+2x+x=27 bcoz when i read this question i did in this way only but when after
I saw this answer it was different.

SO PLZ TELL ME SOME TIPS HOW 2 IDENTIFY THIS IS BELONGS 2 THIS METHODS

Ganesh said:   1 decade ago
A=2+B,
B=2C

A+B+C=27
so (2+B) + B + B/2 = 27
2B + B/2 = 25
5B/2 = 25
B=10

Ilaks said:   1 decade ago
@shalini

Read the ques properly.

Assume C=X. it is given that A IS 2 YEARS OLDER THAN B. It means that we should ADD the 2 years to B's age, so A=B+2.

Then for C it is given that it was TWICE AS OLD AS C. so it is understood tat it should be MULTIPLIED WITH THE C'S AGE. so B=2X.

Finally, sub B=2X in A's equation(A=B+2). therefore A=2X+2

Now A+B+C=27, therefore sub the values of A,B,C in the equation

2X+2+2X+X=27
5X+2=27
5X=27-2
5X=25
X=5.


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