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0.99999999/1.0001 - 0.99999991/1.0003 =
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29 May 2020, 11:14
29 May 2020, 11:14
Expert Reply
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64% (01:40) correct
35% (01:13) wrong based on 31 sessions
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\(\frac{0.99999999}{1.0001}-\frac{0.99999991}{1.0003}=\)
(A) \(10^{(-8)}\)
(B) \(3*10^{(-8)}\)
(C) \(3*10^{(-4)}\)
(D) \(2*10^{(-4)}\)
(E) \(10^{(-4)}\)
(A) \(10^{(-8)}\)
(B) \(3*10^{(-8)}\)
(C) \(3*10^{(-4)}\)
(D) \(2*10^{(-4)}\)
(E) \(10^{(-4)}\)
Re: 0.99999999/1.0001 - 0.99999991/1.0003 =
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29 May 2020, 11:15
29 May 2020, 11:15
Expert Reply
Post A Detailed Correct Solution For The Above Questions And Get A Kudos.
Question From Our New Project: GRE Quant Challenge Questions Daily - NEW EDITION!
Question From Our New Project: GRE Quant Challenge Questions Daily - NEW EDITION!
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Re: 0.99999999/1.0001 - 0.99999991/1.0003 =
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29 May 2020, 11:18
29 May 2020, 11:18
2
Carcass wrote:
\(\frac{0.99999999}{1.0001}-\frac{0.99999991}{1.0003}=\)
(A) \(10^{(-8)}\)
(B) \(3*10^{(-8)}\)
(C) \(3*10^{(-4)}\)
(D) \(2*10^{(-4)}\)
(E) \(10^{(-4)}\)
(A) \(10^{(-8)}\)
(B) \(3*10^{(-8)}\)
(C) \(3*10^{(-4)}\)
(D) \(2*10^{(-4)}\)
(E) \(10^{(-4)}\)
One approach is to combine the fractions and then use some approximation.
First combine the fractions by finding a common denominator.
(9999.9999)/(10001) - (9999.9991)/(10003)
= (9999.9999)(10003)/(10001)(10003) - (9999.9991)(10001) /(10003)(10001)
= [(10003)(9999.9999) - (10001)(9999.9991)] / (10001)(10003)
= [(10003)(10^4) - (10001)(10^4)] / (10^4)(10^4) ... (approximately)
= [(10003) - (10001)] / (10^4) ... (divided top and bottom by 10^4)
= 2/(10^4)
= 2*10^(-4)
= D
Cheers,
Brent
