Is it A?pzazz12 wrote: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, the how old is B?
(A)10
(B)33
(C)7
(D)8
(E)11
A=B+2
B=2C
A+B+C=27
B+2 + B + B/2 = 27
Solving for B , you will get B =10
An intresting question from ps..............
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A=B+2
B=2C
A+B+C=27
B+2 + B + B/2 = 27
Solving for B , you will get B =10
There is another way to solve the question without using the equation.
Since B is twice old as C and age cannot be in fraction, therefore age of B will be always even number.
So you can easily eliminate choices (B) (C) and (E).
Now if you choose (A),
then B = 10, A = 12 and C = 5
Total = 27
Choose (A).
However, this method may not be applicable for all question but somehow it work for this question.
Enjoy!!!
Since B is twice old as C and age cannot be in fraction, therefore age of B will be always even number.
So you can easily eliminate choices (B) (C) and (E).
Now if you choose (A),
then B = 10, A = 12 and C = 5
Total = 27
Choose (A).
However, this method may not be applicable for all question but somehow it work for this question.
Enjoy!!!
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I am born to fly, not to live in boundaries
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kaushiksin
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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, the how old is B?
It gives a simple equation i.e.
A+B+C = 27
=> B+2+B+B/2 = 27
=> 5B = 50
=> B = 10
Hence the answer is (A)
It gives a simple equation i.e.
A+B+C = 27
=> B+2+B+B/2 = 27
=> 5B = 50
=> B = 10
Hence the answer is (A)
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Brian@VeritasPrep
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Hey guys,
These age problems are great examples of a thought process that I think is extremely helpful on this test for any word problems:
The word "IS" (or any form of the verb "to be") means "equals" (=). So when converting word problems to equations, let that word IS be your guide:
A is two years older than B
A = 2 years older than B
A = 2 + B
B is twice as old as C
B = twice C
B = 2C
Now you have pure math to work with, and you're asked to solve for B (we also have the equation A + B + C = 27), so you' ll want to put all of the equations in terms of B:
A = 2 + B
C = B/2
So: (2 + B) + B + (B/2) = 27
2B + B/2 + 2 = 27
2B + B/2 = 25
(find a common denominator for the B terms: 4B/2 + B/2 = 5B/2)
5B/2 = 25
5B = 50
B = 10
When approaching word problems, keep in mind that they almost always give you the operations just in word form.
Is --> =
More than ---> +
Of ---> * (multiplication)
Per ---> divided by
Percent ---> /100
etc.
Get used to making these quick translations and you can make word problems pretty easy to set up.
These age problems are great examples of a thought process that I think is extremely helpful on this test for any word problems:
The word "IS" (or any form of the verb "to be") means "equals" (=). So when converting word problems to equations, let that word IS be your guide:
A is two years older than B
A = 2 years older than B
A = 2 + B
B is twice as old as C
B = twice C
B = 2C
Now you have pure math to work with, and you're asked to solve for B (we also have the equation A + B + C = 27), so you' ll want to put all of the equations in terms of B:
A = 2 + B
C = B/2
So: (2 + B) + B + (B/2) = 27
2B + B/2 + 2 = 27
2B + B/2 = 25
(find a common denominator for the B terms: 4B/2 + B/2 = 5B/2)
5B/2 = 25
5B = 50
B = 10
When approaching word problems, keep in mind that they almost always give you the operations just in word form.
Is --> =
More than ---> +
Of ---> * (multiplication)
Per ---> divided by
Percent ---> /100
etc.
Get used to making these quick translations and you can make word problems pretty easy to set up.
Brian Galvin
GMAT Instructor
Chief Academic Officer
Veritas Prep
Looking for GMAT practice questions? Try out the Veritas Prep Question Bank. Learn More.
GMAT Instructor
Chief Academic Officer
Veritas Prep
Looking for GMAT practice questions? Try out the Veritas Prep Question Bank. Learn More.
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GMATGuruNY
- GMAT Instructor
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We can just plug in the answers, which represent the age of B. Since B is twice as old as C and the sum of the ages is an integer (27), B's age must be even. Eliminate B, C and E.msbinu wrote:pzazz12 wrote: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, the how old is B?
(A)10
(B)33
(C)7
(D)8
(E)11
Answer choice A:
B= 10
C = 5 (Since B is twice as old)
A = 12 (Since A is 2 years older than B)
A+B+C = 12+10+5 = 27. Success!
The correct answer is A.
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Followed here and elsewhere by over 1900 test-takers.
I have worked with students based in the US, Australia, Taiwan, China, Tajikistan, Kuwait, Saudi Arabia -- a long list of countries.
My students have been admitted to HBS, CBS, Tuck, Yale, Stern, Fuqua -- a long list of top programs.
As a tutor, I don't simply teach you how I would approach problems.
I unlock the best way for YOU to solve problems.
For more information, please email me (Mitch Hunt) at [email protected].
Student Review #1
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Student Review #3
