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If 0.0015*10^m/0.03*10^k=5*10^7, then m - k =
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04 Jun 2020, 08:54
04 Jun 2020, 08:54
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30% (01:05) wrong based on 59 sessions
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If \(\frac{0.0015*10^m}{0.03*10^k}=5*10^7\), then m - k =
(A) 9
(B) 8
(C) 7
(D) 6
(E) 5
(A) 9
(B) 8
(C) 7
(D) 6
(E) 5
Re: If 0.0015*10^m/0.03*10^k=5*10^7, then m - k =
[#permalink]
04 Jun 2020, 08:54
04 Jun 2020, 08:54
Expert Reply
Post A Detailed Correct Solution For The Above Questions And Get A Kudos.
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Re: If 0.0015*10^m/0.03*10^k=5*10^7, then m - k =
[#permalink]
04 Jun 2020, 08:57
04 Jun 2020, 08:57
Carcass wrote:
If \(\frac{0.0015*10^m}{0.03*10^k}=5*10^7\), then m - k =
(A) 9
(B) 8
(C) 7
(D) 6
(E) 5
(A) 9
(B) 8
(C) 7
(D) 6
(E) 5
One approach is to assign k a "nice" value.
Let's see what happens when k = 0
We get: (0.0015 x 10^m) / (0.03 x 10^0) = 5 x 10^7
Simplify: (0.0015 x 10^m) / (0.03 x 1) = 5 x 10^7
Simplify: (0.0015 x 10^m) / (0.03) = 5 x 10^7
Multiply both sides by 0.03 to get: 0.0015 x 10^m = 0.15 x 10^7
Eliminate blue decimals by multiplying both sides by 10,000 to get: 15 x 10^m = 1500 x 10^7
Divide both sides by 15 to get: 1 x 10^m = 100 x 10^7
Rewrite 100 as 10^2: 1 x 10^m = 10^2 x 10^7
Simplify: 10^m = 10^9
So, m = 9
In other words, when k = 0, m = 9
So, m - k = 9 - 0 = 9
Answer: A
Cheers,
Brent
