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555-605 (Medium)|   Arithmetic|   Percent and Interest Problems|                  
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If there are 664,579 prime numbers among the first 10 millio 26 Dec 2013, 09:02
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If there are 664,579 prime numbers among the first 10 million positive integers, approximately what percent of the first 10 million positive integers are prime numbers?

(A) 0.0066%
(B) 0.066%
(C) 0.66%
(D) 6.6%
(E) 66%
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D
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Bunuel
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If there are 664,579 prime numbers among the first 10 millio 26 Dec 2013, 09:02
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SOLUTION

If there are 664,579 prime numbers among the first 10 million positive integers, approximately what percent of the first 10 million positive integers are prime numbers?

(A) 0.0066%
(B) 0.066%
(C) 0.66%
(D) 6.6%
(E) 66%

We need to find 664,579 is what percent of 10 million: \(\frac{664,579}{10,000,000}*100\approx{6.6%}\).

Answer: D.
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If there are 664,579 prime numbers among the first 10 millio 26 Dec 2013, 21:00
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664579=x/100 * 10,000,000 = approx. 6.6%

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If there are 664,579 prime numbers among the first 10 millio 26 Dec 2013, 22:50
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664,579 = (x/100) * 10^7;
664, 579 = x * 10^5
=> x = 664, 579/10^5 = 6.64579 ~ 6.6%

Ans is (D).
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If there are 664,579 prime numbers among the first 10 millio 27 Dec 2013, 01:37
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Writing\(664,579\) as \(0.66 * 10^6\)
Percentage of prime numbers in 10 million numbers \(= ( (0.66 * 10^6)/(10*10^6))* 100=6.6%\)

Answer: Option (D)
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If there are 664,579 prime numbers among the first 10 millio 30 Dec 2013, 05:14
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If there are 664,579 prime numbers among the first 10 million positive integers, approximately what percent of the first 10 million positive integers are prime numbers?

(A) 0.0066%
(B) 0.066%
(C) 0.66%
(D) 6.6%
(E) 66%

Sol: Given there 664 579 prime nos in first 10 million positive integers.So % will be

(0.664579*10^6/10 *10^6)*100 ------> 0.664579*10 and thus 6.6%
Ans D
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If there are 664,579 prime numbers among the first 10 millio 02 Jan 2014, 05:56
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10 million is 10 x 10^6 = 10^7

(664 579/10^7) x 10^2 = 6.6 %

Answer D
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If there are 664,579 prime numbers among the first 10 millio 27 Aug 2014, 03:49
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100,000 is 1 % of 10,000,000 hence 664,579 will be approx. 6.6% of 10,000,000.
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If there are 664,579 prime numbers among the first 10 millio 31 Mar 2015, 06:56
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664,579 / 10,000,000 *100 =x%

you can reduce the 10 million by 100, so that you only have 100,000 in the denominator. Now, bot the nominator and denominator have the same amount of digits and from this point you can ask yourself how much for e.g. 664/100 is. The solution is 6,64 or in this case 6,6%
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If there are 664,579 prime numbers among the first 10 millio 31 Mar 2015, 11:24
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Bunuel
If there are 664,579 prime numbers among the first 10 million positive integers, approximately what percent of the first 10 million positive integers are prime numbers?

(A) 0.0066%
(B) 0.066%
(C) 0.66%
(D) 6.6%
(E) 66%
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664579/10 million
= 664579/100,000,00
= 0.066
= 0.066 * 100%
= 6.6%

Hence option (D).

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If there are 664,579 prime numbers among the first 10 millio 14 Aug 2025, 14:42
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