A, B, C are three consecutive positive integers (ABC). What is the

Question

A, B, C are three consecutive positive integers (A>B>C). What is the value of the expression 2A +B +3C?

A. 6A+7.
B. 5A+1.
C. 5A-1.
D. 6A-5.
E. 6A-7.

Nightfury14 · Accepted Answer

A, B, C are three consecutive positive integers (A>B>C). What is the value of the expression 2A +B +3C?

=> A+A+(A-1)+3(A-2)
Ans E. 6A-7.

Good luck
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BrentGMATPrepNow · Answer

Here's another approach:

Let the three consecutive positive integers be 1, 2 and 3
That is, A = 3, B = 2, C = 1

What is the value of the expression 2A +B +3C?  
Well, if A = 3, B = 2, C = 1, then 2A +B +3C = 2(3) +2 +3(1) = 11

So, when A =  3 , we find that A +B +3C =  11 
Now test the answer choices, to see which one yields an output of  11 , when A =  3

A. 6( 3 ) + 7 =  25  ELIMINATE
B. 5( 3 ) + 1 =  16  ELIMINATE
C. 5( 3 ) - 1 =  14  ELIMINATE
D. 6( 3 ) - 5 =  13  ELIMINATE
E. 6( 3 ) - 7 =  11  KEEP

Answer:  E

Skywalker18 · Answer

A= C+2
=> C = A-2
A= B+1
=> B = A-1

Since the answer options contain variable A , we have to write B and C in terms of A .
2A +B +3C = 2A + (A-1) +3(A-2)
=2A + A-1 + 3A -6
=6A -7
Answer E

Divyadisha · Answer

B = A-1
C= A-2

Putting these values in 2A +B +3C we get 6A-7

E is the answer

sasyaharry · Answer

Assign some simple values, A=3, B=2, C=1
2A+B+3C = 11
For questions of these type where GMAT asks the value, I always start from E.
Lo and behold.  E  is the answer because 6*3-7=11

generis · Answer

A > B > C
3 > 2 > 1
A>(A-1)>(A-2)

What is 2A + B + 3C?

(2)(A) + (A-1) + 3(A-2) =

2A + A - 1 + 3A - 6 =

6A - 7. Answer E

Mehemmed · Answer

Just for curiosity...I've tried another method to test:
(A+1) for A;
(A) for B;
(A-1) for C

Since A>B>C, it would be (A-1)A(A+1)- three consecutive integers. Then plugging in given calculation : 2A+B+3C, we will get the following:

2(A+1)+A+3(A-1)= 2A+2+A+3A-3=6A-1

What I miss here?

Keepushinalmosthere · Answer

Damn I feel like a loser for getting it wrong. I picked A...

Shiv2016 · Answer

Bunuel

I tried to solve it by two ways but only one works in this case. Please explain why so?

A= a
B=a-1
C= a-2

We will get E as the answer after plugging in these values in the expression given.

But if we take:

A= a+2
B= a+1
C= a

2a+4+ a+1+ 3a
= 6a+ 5

Where did I go wrong in the second method?

Bunuel · Answer

We need the value in terms of A. What is A in your second method? A = a + 2, so a = A - 2. Thus, 6a+ 5 = 6(A - 2) + 5 = 6A - 7 (Answer: E).

shashankism · Answer

Since A, B, C are three consecutive integers (A>B>C)

C = A-2
B = A-1

So, 2A+B+3C = 2A + A-1 +3 (A-2) = 6A - 7

Answer E

ScottTargetTestPrep · Answer

Since the integers A, B, and C are consecutive integers (with A > B > C) and we see that the answer choices are in terms of A, we can say B = A - 1 and C = A - 2. Thus:

2A + B + 3C = 2A + A - 1 + 3(A - 2) = 3A - 1 + 3A - 6 = 6A - 7

Answer: E

TheKingInTheNorth · Answer

2 ways of doing it 
1.
let a,b,c = x, x-1, x-2 and then apply the condition which will get us E

2. 
let a, b, c = x+2,x+1,x and then apply the condition ....but in this case the value is not present in the option .

either approach can be taken depending on the value of the option .

abhishekdadarwal2009 · Answer

Simply assume three consecutive numbers and do POI in the answer choices.
let A=8,B=7 and C=6. Since A>B>C

2A+B+3C=41.
option E gives 48-7=41

OPtion E is the correct choice.

bumpbot · Answer

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