If the product of the integers a, b, c, and d is 1,155 and if a > b > c > d > 1, then what is the value of a - d?
(A) 2
(B) 8
(C) 10
(D) 11
(E) 14
The OA is the option B.
How can I determine the value of a, b, c and d? What is the best approach to finding them? Experts, can you help me?
If the product of the integers a, b, c, and d is
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Hi M7MBA,
We're told that the product of the integers A, B, C and D is 1,155 and A > B > C > D > 1. We're asked for the value of A - D. This question comes down to 'prime factorization' and a bit of Arithmetic.
We know that the 4 variables are INTEGERS and we know that they are DIFFERENT from one another. To define those values, we have to 'break down' the product (1155) into its pieces.
1155 =
(5)(231) =
(5)(3)(77) =
(5)(3)(7)(11)
Given the inequality... A=11, B=7, C=5 and D=3... so (A - D) = (11 - 3) = 8
Final Answer: B
GMAT assassins aren't born, they're made,
Rich
We're told that the product of the integers A, B, C and D is 1,155 and A > B > C > D > 1. We're asked for the value of A - D. This question comes down to 'prime factorization' and a bit of Arithmetic.
We know that the 4 variables are INTEGERS and we know that they are DIFFERENT from one another. To define those values, we have to 'break down' the product (1155) into its pieces.
1155 =
(5)(231) =
(5)(3)(77) =
(5)(3)(7)(11)
Given the inequality... A=11, B=7, C=5 and D=3... so (A - D) = (11 - 3) = 8
Final Answer: B
GMAT assassins aren't born, they're made,
Rich
GMAT/MBA Expert
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- Joined: Thu Apr 09, 2015 9:34 am
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We can start by expressing 1,155 as the product of its prime factors.M7MBA wrote:If the product of the integers a, b, c, and d is 1,155 and if a > b > c > d > 1, then what is the value of a - d?
(A) 2
(B) 8
(C) 10
(D) 11
(E) 14
1,155 = 5 x 231 = 5 x 77 x 3 = 5 x 7 x 11 x 3
This means that a = 11, b = 7, c = 5, and d = 3.
Thus, a - d = 11 - 3 = 8.
Answer: B
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