GRE Prep Club Daily Prep
Thank you for using the timer - this advanced tool can estimate your performance and suggest more practice questions. We have subscribed you to Daily Prep Questions via email.
Customized
for You
Track
Your Progress
Practice
Pays
Not interested in getting valuable practice questions and articles delivered to your email? No problem, unsubscribe here.
a-(1/b)=/0
[#permalink]
Updated on: 22 Jan 2021, 13:41
Updated on: 22 Jan 2021, 13:41
00:00
Question Stats:
100% (00:27) correct
0% (00:00) wrong based on 4 sessions
Hide Show timer Statistics
Quantity A |
Quantity B |
The reciprocal of \(a-(\frac{1}{b})\) |
\(\frac{b}{(ab-1)}\) |
A) Quantity A is greater.
B) Quantity B is greater.
C) The two quantities are equal.
D) The relationship cannot be determined from the information given.
Why is the answer C?
Any two numbers whose product equal positive 1 are reciprocals. The reciprocal of a fraction is not just the "flip" of the fraction.
E.g. The reciprocal of √3 can be (√3)/3
Therefore, the reciprocal of a-(1/b) might not just be b/(ab-1)? So the answer should be D?
a-(1/b)=/0
[#permalink]
22 Jan 2021, 13:42
22 Jan 2021, 13:42
Expert Reply
Please Sir format the QCQ questions like you see now.
Follow the instructions in one easy step
https://gre.myprepclub.com/forum/how-to-po ... 12752.html
\(\frac{a-1}{b}\)
\(\frac{ab-1}{b}\)
The reciprocal
\(\frac{b}{ab-1}\)
The two quantities are equal
reciprocal_fraction_example.jpg [ 12.5 KiB | Viewed 1815 times ]
For better understanding see our Quant book https://gre.myprepclub.com/forum/gre-math- ... -2609.html
Regards
Follow the instructions in one easy step
https://gre.myprepclub.com/forum/how-to-po ... 12752.html
\(\frac{a-1}{b}\)
\(\frac{ab-1}{b}\)
The reciprocal
\(\frac{b}{ab-1}\)
The two quantities are equal
Quote:
The reciprocal of a fraction is just switching the numerator (top number) and the denominator (bottom number).
Attachment:
reciprocal_fraction_example.jpg [ 12.5 KiB | Viewed 1815 times ]
For better understanding see our Quant book https://gre.myprepclub.com/forum/gre-math- ... -2609.html
Regards
Re: a-(1/b)=/0
[#permalink]
23 Jan 2021, 15:42
23 Jan 2021, 15:42
I solved this problem using the matching operations method. Quantity A can be written as 1/(a-(1/b)). Multiply both sides by a-(1/b) and ab-1 and you are left with ab-1 on both sides of the equation. Thus C is the correct answer. Alternatively, you could solve using test values. For instance, if a=2 and b=2, both quantities will equal 2/3.
