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0.99999999/1.0001 - 0.99999991/1.0003 =

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Carcass
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0.99999999/1.0001 - 0.99999991/1.0003 = [#permalink] New post   29 May 2020, 11:14
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0.999999991.0001−0.999999911.0003=


(A) 10(−8)

(B) 3∗10(−8)

(C) 3∗10(−4)

(D) 2∗10(−4)

(E) 10(−4)
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Re: 0.99999999/1.0001 - 0.99999991/1.0003 = [#permalink] New post   29 May 2020, 11:15
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Post A Detailed Correct Solution For The Above Questions And Get A Kudos.
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Re: 0.99999999/1.0001 - 0.99999991/1.0003 = [#permalink] New post   29 May 2020, 11:18
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Carcass wrote:
0.999999991.0001−0.999999911.0003=


(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
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Re: 0.99999999/1.0001 - 0.99999991/1.0003 = [#permalink] New post   12 Aug 2021, 12:40
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Re: 0.99999999/1.0001 - 0.99999991/1.0003 = [#permalink]
12 Aug 2021, 12:40
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