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What percent of b is a? (1) (b  a)b = 2/5 (2) b = 50
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26 Nov 2019, 22:56
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Competition Mode Question What percent of b is a? (1) \(\frac{ba}{b}=\frac{2}{5}\) (2) \(b=50\)
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Re: What percent of b is a? (1) (b  a)b = 2/5 (2) b = 50
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27 Nov 2019, 00:03
What percent of b is a? Let x% of b is a —> x/100*b = a —> x = 100a/b
(1) (b  a)/b = 2/5 —> 1  a/b = 2/5 —> a/b = 1  2/5 = 3/5
So, x = 100*3/5 = 60 —> Sufficient
(2) b = 50 Nothing can be said about “a” —> Insufficient
IMO Option A
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Re: What percent of b is a? (1) (b  a)b = 2/5 (2) b = 50
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27 Nov 2019, 00:41
What percent of b is a...........i.e a/b value
(1) b−a/b=2/5.......5b5a=2b, 3b=5a, a/b= 3/5 = 60%.............SUFFICIENT
(2) b=50..........INSUFFICIENT
OA:A



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Re: What percent of b is a? (1) (b  a)b = 2/5 (2) b = 50
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27 Nov 2019, 06:24
We are to determine the percentage of b with respect to a. In order to do the aforementioned task, it is imperative to know either the values of a and b or the relationship between a and b.
Statement 1: (ba)/b = 2/5 Statement 1 is sufficient. we can tell that b=5. and if ba=2, then a=3. Hence we can determine the percentage of b with respect to a.
Statement 2: b=50 This is not sufficient since we don't have any information on the value of a. Therefore a can assume infinitely many values that can lead to different percentages.
The answer is option A.



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Re: What percent of b is a? (1) (b  a)b = 2/5 (2) b = 50
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27 Nov 2019, 07:02
A b*(k/100)= a k= 100(a/b) From first a/b can be calculated.



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Re: What percent of b is a? (1) (b  a)b = 2/5 (2) b = 50
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27 Nov 2019, 07:33
x/100*b = a x= a*100/b #1 b−a/b=2/5 a/b = 3/5 sufficient #2 b=50 insufficient IMO A
What percent of b is a?
(1) b−a/b=2/5
(2) b=50



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Re: What percent of b is a? (1) (b  a)b = 2/5 (2) b = 50
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27 Nov 2019, 07:36
What percent of b is a? This can be written as \(a=\frac{x}{100}*b....x=100*\frac{a}{b}\) So we require to know the value of \(\frac{a}{b}\). (1) \(\frac{ba}{b}=\frac{2}{5}.........1\frac{a}{b}=\frac{2}{5}.........1\frac{2}{5}=\frac{3}{5}=\frac{a}{b}.........\) (2) \(b=50\)..Nothing about a. A
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Re: What percent of b is a? (1) (b  a)b = 2/5 (2) b = 50
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27 Nov 2019, 07:39
We need to know a/b or b/a to determine what percentage of b is a.
(1) (ba)/b = 2/5 This statement gives us information about a/b and thus, we can determine what percentage of b is a. SUFFICIENT
(2) b=50 We don't know a and hence, we can't determine what percentage of b is a. NOT SUFFICIENT.
Final answer is (A)
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Re: What percent of b is a? (1) (b  a)b = 2/5 (2) b = 50
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27 Nov 2019, 09:52
Statement 1 is sufficient. We can transform the equation and get a/b: \(\frac{(ba)}{b} = \frac{2}{5}\) \(1  \frac{a}{b} = \frac{2}{5}\) \(\frac{a}{b} = 1  \frac{2}{5} = \frac{3}{5} =\frac{6}{10}\)
From the above we know that a = 60% of b.
Statement 2 is not sufficient, because a is not given.
Answer (A).



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Re: What percent of b is a? (1) (b  a)b = 2/5 (2) b = 50
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27 Nov 2019, 15:03
What percent of b is a? —>\(( \frac{x}{100})*b= a\) \(x = 100(\frac{a}{b})\) ???
(Statement1): \(\frac{(b—a)}{b}= \frac{2}{5}\) \(1–(\frac{a}{b}) = \frac{2}{5}\) \((\frac{a}{b}) = \frac{3}{5}\) —> \(x= 100(\frac{a}{b})= 100(\frac{3}{5})= 60\) Sufficient
(Statement2): b= 50 \(x= 100(\frac{a}{b})= 100(\frac{a}{50})= 2a\) No info about what a is. —> a could be any number Insufficient
The answer is A
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Re: What percent of b is a? (1) (b  a)b = 2/5 (2) b = 50
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27 Nov 2019, 15:03






