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.
The OA is E.
What is the best approach to solve this PS question? Experts, can you help me?
A, B, C are three consecutive positive integers (A>B>C
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Here's one approach:M7MBA wrote: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.
The OA is E.
What is the best approach to solve this PS question? Experts, can you help me?
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
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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:M7MBA wrote: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
2A + B + 3C = 2A + A - 1 + 3(A - 2) = 3A - 1 + 3A - 6 = 6A - 7
Answer: E
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