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If the quotient a/b positive, which of the following must be [#permalink]
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03 Sep 2012, 05:49
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Re: If the quotient a/b positive, which of the following must be [#permalink]
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03 Sep 2012, 05:49



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Re: If the quotient a/b positive, which of the following must be [#permalink]
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03 Sep 2012, 06:10
a and be must have the same sign. Either both are positive or both are negative.
When multiplying a*b, the result will therefore be positive.
Answer C.



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Re: If the quotient a/b positive, which of the following must be [#permalink]
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05 Sep 2012, 07:14
I think the best approach in such questions is to plug in numbers Since the question asks about must be true then any numbers should qualify, if a/b is positive then a and b have the same sign so a*b must be positive. (C)
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Re: If the quotient a/b positive, which of the following must be [#permalink]
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05 Sep 2012, 19:55
a/b implies a and b have the same sign.
a<0 AND b<0
or
a>0 AND b>0
A. a>0 does not have to be true, a can be negative B. b>0 does not have to be true, b can be negative C. ab>0, has to be true since a AND b have the same sign D. ab>0 does not have to be true since a AND b can be negative and the result of ab can be negative E. a+b>0 does not have to be true since a AND b can be negative and the result of a+b can be negative
Answer: C.



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Re: If the quotient a/b positive, which of the following must be [#permalink]
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07 Sep 2012, 03:14



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Re: If the quotient a/b positive, which of the following must be [#permalink]
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14 Jun 2013, 19:23
Hi Bunuel, what if a=0;b=2. we have a/b as positive as a result ab = 0. C fails.(:D is this some kind of miss in the question or Am i missing my basics here) Tx Bunuel wrote: SOLUTION
If the quotient a/b positive, which of the following must be true?
(A) a > 0 (B) b > 0 (C) ab > 0 (D) ab > 0 (E) a+b > 0
\(\frac{a}{b}>0\) means \(a\) and \(b\) have the same sign, either both are negative or both are positive. Thus, their product will also be positive: \(ab>0\).
Answer: C.
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Re: If the quotient a/b positive, which of the following must be [#permalink]
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15 Jun 2013, 00:56



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If the quotient a/b positive, which of the following must be [#permalink]
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10 Jul 2014, 02:35
For \(\frac{a}{b} > 0\), I took help of numbers: \(\frac{6}{3} = 2 & \frac{6}{3} = 2\) Checking all options: A: a>0 ............ Fail for a = 6; b = 3 B: b>0 ............... Fail for a = 6; b = 3 C: ab>0 ................ OK for both (6*3 = 18 & 6 * 3 = 18)D: ab > 0 ........... Fail for a = 6; b = 3 E: a+b > 0 ........... Fail for a = 6; b = 3 Answer = C
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If the quotient a/b positive, which of the following must be [#permalink]
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09 May 2016, 13:35
\(\frac{a}{b}\) is positive means \(\frac{a}{b}\) > 0
This means that both a and b are either negative or both a and b are positive So quotient \(\frac{a}{b}\) will always be positive ab > 0 correct answer  C



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Re: If the quotient a/b positive, which of the following must be [#permalink]
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10 May 2016, 07:26
Bunuel wrote: If the quotient a/b positive, which of the following must be true?
(A) a > 0 (B) b > 0 (C) ab > 0 (D) ab > 0 (E) a+b > 0
We are given that a divided by b is positive (or greater than zero). We know that in division when a quotient is positive, the two numbers being divided are either both negative or both positive. This is also the case in multiplication; that is, to get a product that is positive, we must multiply two positive numbers or two negative numbers. Thus the only answer choice that MUST be positive is C, ab > 0.
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Fractions  OG 13E [#permalink]
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04 Sep 2016, 08:47
1. If the quotient a/b is positive, which of the following must be true?
(A) a>0 (B) b>0 (0 ab>0 (D) ab>0 (E) a + b>0
Regards, MoM



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Re: If the quotient a/b positive, which of the following must be [#permalink]
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04 Sep 2016, 10:21
Manonamission wrote:
1. If the quotient a/b is positive, which of the following must be true?
(A) a>0 (B) b>0 (0 ab>0 (D) ab>0 (E) a + b>0
Regards, MoM
a/b positive means both a and b MUST of same sign. Hence, ab>0. Answer is C
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Re: If the quotient a/b positive, which of the following must be [#permalink]
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01 Apr 2017, 07:14
Its clearly C a/b= Positive (Thus either both are positive or both are negative) ab>0 a b Positive * Positive =Positive Negative * Negative =Positive
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Re: If the quotient a/b positive, which of the following must be [#permalink]
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17 Apr 2018, 09:42
Bunuel wrote: If the quotient a/b positive, which of the following must be true? (A) a > 0 (B) b > 0 (C) ab > 0 (D) ab > 0 (E) a+b > 0 Practice Questions Question: 32 Page: 156 Difficulty: 550 The key word here is MUSTSo, if we can find values of a and b that make an answer choice FALSE, then we can eliminate that answer choice. For example, a = 3 and b = 1 satisfies the given condition that a/b is positive [since (3)/(1) = 3, and 3 is positive]Now take the answer choices and plug in a = 3 and b = 1We get: (A) 3 > 0. FALSE. ELIMINATE A (B) 1 > 0. FALSE. ELIMINATE B (C) ( 3)( 1) > 0 TRUE. KEEP C (D) ( 3)  ( 1) > 0. FALSE. ELIMINATE D (E) ( 3) + ( 1) > 0. FALSE. ELIMINATE E By the process of elimination, the correct answer is C Cheers, Brent
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