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?
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.
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.
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.
NARESH said:
1 decade ago
Hi dude............
females(Y)=6000,males(X)=18000
x+y=24000........................(1)
(106/100)x+(109/100)y=25620.......(2)
by solving this 2 u get before increasing values..........
after increasing total number of females are (109/100)*6000=6540
after increasing total number of males are (106/100)*18000=19080
total is 25620
Hence proved(any doubts?)
females(Y)=6000,males(X)=18000
x+y=24000........................(1)
(106/100)x+(109/100)y=25620.......(2)
by solving this 2 u get before increasing values..........
after increasing total number of females are (109/100)*6000=6540
after increasing total number of males are (106/100)*18000=19080
total is 25620
Hence proved(any doubts?)
Shahid101 said:
9 years ago
Lets.
A=B+2.
From this we have B=A-2.
Then, B=2C.
We have C=B/2.
Add all these,
A + B + C = 27.
Put the values of A B and C.
B + 2 + A-2 + B/2 =27.
After solving, we will have.
3B + 2A = 54.
We want B's age, so put that value of B which is in terms of A.
3B+2 (B+2) =54.
Ultimately we have B=10.
Correct me if I'm mistaken anywhere, please.
A=B+2.
From this we have B=A-2.
Then, B=2C.
We have C=B/2.
Add all these,
A + B + C = 27.
Put the values of A B and C.
B + 2 + A-2 + B/2 =27.
After solving, we will have.
3B + 2A = 54.
We want B's age, so put that value of B which is in terms of A.
3B+2 (B+2) =54.
Ultimately we have B=10.
Correct me if I'm mistaken anywhere, please.
(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
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)
Shajil george said:
1 decade ago
Let the age of c is x
Given that the age of b is twice of c age so,
b is age is 2x
Similarly
a is two years grater than b is age, so,
a is 2x+x
From the Question
The sum of a,b,c is 27
Then,
2x+2+2x+x=27
5x+2=27
5x=27-2
5x=25
x=25/5
=5
So,the age of b is 2x,
The value of x is 5
So the age of bis 10.
Given that the age of b is twice of c age so,
b is age is 2x
Similarly
a is two years grater than b is age, so,
a is 2x+x
From the Question
The sum of a,b,c is 27
Then,
2x+2+2x+x=27
5x+2=27
5x=27-2
5x=25
x=25/5
=5
So,the age of b is 2x,
The value of x is 5
So the age of bis 10.
Anuj rojlove said:
1 decade ago
Friends this question solve easy trick.
Lets start assume.
C = x.
Then A = 2+B.
But B = 2C {its twice of C}.
So B = 2x {C = x (assume)}.
Now question.
A+B+C = 27.
(2+2x)+2x+x = 27.
= 2+5x = 27.
= 5x = 27-2.
= 5x = 25.
x = 5.
Then B = 2x (how old B).
B = 2*5.
B = 10 (answer).
Lets start assume.
C = x.
Then A = 2+B.
But B = 2C {its twice of C}.
So B = 2x {C = x (assume)}.
Now question.
A+B+C = 27.
(2+2x)+2x+x = 27.
= 2+5x = 27.
= 5x = 27-2.
= 5x = 25.
x = 5.
Then B = 2x (how old B).
B = 2*5.
B = 10 (answer).
P.GANGADHAR said:
8 years ago
A is x.
B is x-2.
C is (x-2)/2.
The sum of all ages is 27.
x+ (x-2)+ (x-2)/2 = 27.
(x-2+2x-4+2x) / 2 = 27.
Then (x+2x-6+2x) = 54.
(5x-6) =54.
5x =60.
x= 12 then.
(A is 12).
B is (x- 2 = 12-2= 10).
B age is 10.
B is x-2.
C is (x-2)/2.
The sum of all ages is 27.
x+ (x-2)+ (x-2)/2 = 27.
(x-2+2x-4+2x) / 2 = 27.
Then (x+2x-6+2x) = 54.
(5x-6) =54.
5x =60.
x= 12 then.
(A is 12).
B is (x- 2 = 12-2= 10).
B age is 10.
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
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
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....
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....
Hayat said:
10 years ago
Let B=x.
Then according to 1st condition.
A=2+B (B=x).
So A=2+x.
2nd condition B=2C so C=B/2 (B=x).
C=x/2.
Add A, B and C.
A+B+C=27.
(2+x) + (2 (x/2) ) + (x/2) =27.
Simplify the equation.
5x+4=50.
X=10 (option D ans).
Then according to 1st condition.
A=2+B (B=x).
So A=2+x.
2nd condition B=2C so C=B/2 (B=x).
C=x/2.
Add A, B and C.
A+B+C=27.
(2+x) + (2 (x/2) ) + (x/2) =27.
Simplify the equation.
5x+4=50.
X=10 (option D ans).
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