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If a, b, and c are integers and a(b  c) is odd, which of the followin
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23 Jan 2020, 01:08
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If a, b, and c are integers and a(b  c) is odd, which of the following must be odd? A. b B. c C. ab D. ab + c E. abc
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Re: If a, b, and c are integers and a(b  c) is odd, which of the followin
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23 Jan 2020, 04:30
Bunuel wrote: If a, b, and c are integers and a(b  c) is odd, which of the following must be odd?
A. b B. c C. ab D. ab + c E. abc a(b  c) is odd > a = odd & b  c = odd So, Possible combinations of (a, b, c) = (o, e, o) or (o, o, e) A. b > can be odd or even > NoB. c > can be odd or even > NoC. ab = o*o or o*e > NoD. ab + c = o*o + e = o or o*e + o = o > Odd always > YesE. abc = o*o*e = e or o*e*o = e > NoOption D



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If a, b, and c are integers and a(b  c) is odd, which of the followin
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23 Jan 2020, 07:18
Bunuel wrote: If a, b, and c are integers and a(b  c) is odd, which of the following must be odd?
A. b B. c C. ab D. ab + c E. abc Another approach here is to test some values that satisfy the initial condition If a(b  c) is odd, then it COULD be the case that a = 1, b = 2 and c = 1Now let's plug these values into our answer choices... A. b = 2 2 is NOT odd, so eliminate A B. c = 1 1 is odd, so keep B C. ab = (1)(2) = 2 2 is NOT odd, so eliminate C D. ab + c = (1)(2) + 1 = 3 3 is odd, so keep D E. abc = (1)(2)(1) = 2 2 is NOT odd, so eliminate E At this point, we're left with answer choices B and D So that's test another set of values If a(b  c) is odd, then it COULD be the case that a = 2, b = 1 and c = 1Now let's plug these values into the remaining answer choices... B. c = 2 2 is NOT odd, so eliminate B By the process of elimination, the correct answer must be D Cheers, Brent
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Re: If a, b, and c are integers and a(b  c) is odd, which of the followin
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23 Jan 2020, 11:44
Here Odd = o and Even =e a………..b………..c……….a(bc) o………..o……….e……….o*(oe) =o……..First case o………..e……….o……….o*(eo) = o…….Second Case
From the cases above, ab +c = o + e = o ab + c = e + o = o Ans:D



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Re: If a, b, and c are integers and a(b  c) is odd, which of the followin
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23 Jan 2020, 11:54
Question: If a, b, and c are integers and a(b  c) is odd, which of the following must be odd? A. b B. c C. ab D. ab + c E. abc Solution: a(b  c) is odd => a is odd AND (b  c) is odd => a is odd AND b is even and c is odd ... (possibility 1) OR a is odd AND b is odd and c is even ... (possibility 2) Let us check the options: A) b : As discussed above, b could be even or odd  hence, incorrect B) c : As discussed above, b could be even or odd  hence, incorrect C) ab: As discussed above, b could be even or odd => hence, ab could be even or odd  hence, incorrect D) ab + c: According to Possibility (i): odd x even + odd = odd According to Possibility (ii): odd x odd + even = odd Hence, this option is correct E) abc: It is clear that since b or c may be even or odd, abc could also be even or odd  hence, incorrect Answer D
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Re: If a, b, and c are integers and a(b  c) is odd, which of the followin
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29 Jan 2020, 04:51
Bunuel wrote: If a, b, and c are integers and a(b  c) is odd, which of the following must be odd?
A. b B. c C. ab D. ab + c E. abc The only way to obtain an odd product is for both of the factors to be odd, since odd x odd = odd. Since a(b  c) is odd, then a must be odd and (b  c) must be odd, which means b is odd when c is even, or vice versa. Thus, ab will be even when c is odd, or ab will be odd when c is even. In any case, ab + c is odd. Answer: D
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Re: If a, b, and c are integers and a(b  c) is odd, which of the followin
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