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Last year, for every 100 million vehicles that traveled on a
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20 Dec 2012, 08:37
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Last year, for every 100 million vehicles that traveled on a certain highway, 96 vehicles were involved in accidents. If 3 billion vehicles traveled on the highway last year, how many of those vehicles were involved in accidents? (1 billion = 1,000,000,000) (A) 288 (B) 320 (C) 2,880 (D) 3,200 (E) 28,800
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Re: Last year, for every 100 million vehicles that traveled on a
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20 Dec 2012, 08:42
Walkabout wrote: Last year, for every 100 million vehicles that traveled on a certain highway, 96 vehicles were involved in accidents. If 3 billion vehicles traveled on the highway last year, how many of those vehicles were involved in accidents? (1 billion = 1,000,000,000)
(A) 288 (B) 320 (C) 2,880 (D) 3,200 (E) 28,800 3 billion is 30 times as many as 100 million, so for 3 billion vehicles there would be 30*96=2,880 accidents. Answer: C.
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Re: Last year, for every 100 million vehicles that traveled on a
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27 May 2014, 20:00
Walkabout wrote: Last year, for every 100 million vehicles that traveled on a certain highway, 96 vehicles were involved in accidents. If 3 billion vehicles traveled on the highway last year, how many of those vehicles were involved in accidents? (1 billion = 1,000,000,000)
(A) 288 (B) 320 (C) 2,880 (D) 3,200 (E) 28,800 Hello The solution above mine is much easier but I didn't catch it under timing so here's how I solved it. (looks easier on paper for canceling out) (10^8)/96=3x10^9/x x=(96x3x10^9)/10^8 (cancel out 10^9 and 10^8 you get 10) x=96x30=2 880



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Re: Last year, for every 100 million vehicles that traveled on a
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28 May 2014, 12:33
Estimation is helpful here, too. Once you see that you have 30*96, you can say that the answer must be a little less than 30*100, or 3,000. Only C fits. You could also estimate in advance. The accident rate is 96 per 100 million, which is just under 1 in a million. 3 billion divided by a million is 3,000, so again, the answer should be a bit less than 3,000.
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Re: Last year, for every 100 million vehicles that traveled on a
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07 Jul 2016, 09:30
Walkabout wrote: Last year, for every 100 million vehicles that traveled on a certain highway, 96 vehicles were involved in accidents. If 3 billion vehicles traveled on the highway last year, how many of those vehicles were involved in accidents? (1 billion = 1,000,000,000)
(A) 288 (B) 320 (C) 2,880 (D) 3,200 (E) 28,800 To solve we will set up a proportion. We know that “100 million vehicles is to 96 accidents as 3 billion vehicles is to x accidents”. To express everything in terms of “millions”, we can use 3,000 million rather than 3 billion. Creating a proportion we have: 100/96 = 3,000/x Cross multiplying gives us: 100x = 3,000 * 96 x = 30 * 96 = 2,880 The answer is C.
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Re: Last year, for every 100 million vehicles that traveled on a
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14 Mar 2017, 05:51
Walkabout wrote: Last year, for every 100 million vehicles that traveled on a certain highway, 96 vehicles were involved in accidents. If 3 billion vehicles traveled on the highway last year, how many of those vehicles were involved in accidents? (1 billion = 1,000,000,000)
(A) 288 (B) 320 (C) 2,880 (D) 3,200 (E) 28,800 Ans: 96 * 3 = 288; 1000 million = 1 billion so next step is 2880*10 ( as 100 million * 10 = 1000 million = Billion)



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Re: Last year, for every 100 million vehicles that traveled on a
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27 Mar 2018, 08:14
Walkabout wrote: Last year, for every 100 million vehicles that traveled on a certain highway, 96 vehicles were involved in accidents. If 3 billion vehicles traveled on the highway last year, how many of those vehicles were involved in accidents? (1 billion = 1,000,000,000)
(A) 288 (B) 320 (C) 2,880 (D) 3,200 (E) 28,800 We can use equivalent ratios to solve this. # cars/ # accidents: 100,000,000/ 96 = 3,000,000,000/ xRewrite with exponents: 10⁸/ 96 = (3)(10⁹) / xCross multiply to get: (10⁸)(x) = (3)(10⁹)(96) 96 is close enough to 100, so let's replace 96 with 100 to get: (10⁸)(x) = (3)(10⁹)(100) or (10⁸)(x) = (3)(10⁹)(10²) (10⁸)(x) = (3)(10¹¹) Divide both sides by 10⁸ to get: x = (3)(10³) = 3000 We see that both C and D are close to 3000 However, in our calculations, we replaced 96 with 100, so our calculations are a bit HIGHER than they should be. So, the correct answer must be a little smaller than 3000 Answer: C Cheers, Brent
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Re: Last year, for every 100 million vehicles that traveled on a &nbs
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