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While driving from Corvallis to Portland, Matt obeys the speed limit.
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28 Jan 2015, 06:41
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Re: While driving from Corvallis to Portland, Matt obeys the speed limit.
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28 Jan 2015, 08:36
ans D 108mph.. matt covers dist in 81*60/36=135 min.. however vadim has only 13590 min to reach at the same point.. so vadim's speed should just exceed 81/45*60=108mph
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Re: While driving from Corvallis to Portland, Matt obeys the speed limit.
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30 Jan 2015, 20:44
Bunuel wrote: While driving from Corvallis to Portland, Matt obeys the speed limit. Matt’s friend Vadim likes to drive faster than the speed limit and believes that he could leave well after Matt and still reach Portland first. The distance from Corvallis to Portland is 81 miles and both Matt and Vadim travel the same route at their respective constant speeds. If Matt travels at a constant speed of 36 mph and leaves 90 minutes before Vadim, what is the minimum constant speed that Vadim must exceed in order to arrive in Portland before Matt?
A. 72 mph B. 81 mph C. 96 mph D. 108 mph E. 162 mph
Kudos for a correct solution. Matt's time = 81/36 = 9/4 hrs. Therefore, Vadim's time is 9/490 mins = 3/4 hrs. Let Vadim's speed be S. Distance is constant, which we can set as equal. Therefore, 36*9/4=3/4*S. S=108. Answer D.
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Re: While driving from Corvallis to Portland, Matt obeys the speed limit.
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02 Feb 2015, 01:44
Using R*T = D
Matt: 36 * (t + 3/2) = 81 Hence t = 27/36 = 3/4
Now for his friend V: rate * 3/4 = 81 Hence rate = 81*4/3 = 108 Ans D



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Re: While driving from Corvallis to Portland, Matt obeys the speed limit.
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02 Feb 2015, 18:46
Given
Matt Speed = 36 Distance = 81 therefore Matt takes 9/4 hours to travell 81 miles
Vadim starts 90 mins late = 3/2 hours therefore distance travelled bu Vadim in (9/4  3/2) hours is?
(9/43/2) = 3/4 hours
speed of Vadim be x Distance travelled = 81 minimun time = 3/4
x> 81*(4/3) x> 108
Therefore D



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Re: While driving from Corvallis to Portland, Matt obeys the speed limit.
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02 Feb 2015, 23:00
Bunuel wrote: While driving from Corvallis to Portland, Matt obeys the speed limit. Matt’s friend Vadim likes to drive faster than the speed limit and believes that he could leave well after Matt and still reach Portland first. The distance from Corvallis to Portland is 81 miles and both Matt and Vadim travel the same route at their respective constant speeds. If Matt travels at a constant speed of 36 mph and leaves 90 minutes before Vadim, what is the minimum constant speed that Vadim must exceed in order to arrive in Portland before Matt?
A. 72 mph B. 81 mph C. 96 mph D. 108 mph E. 162 mph
Kudos for a correct solution. I too get V's speed to be 108. Since matt travels for 81/36 hours, and V leaves 90 mins or 1.5 hours after him, V travels for (81/361.5) hrs. So his speed is 81/(81/361.5) which comes to 108. But here is where I got confused. The questin asked is what is the minimum speed V must "exceed" to arrive... Is this exceed the speed limit (which is matt's speed =36) or just exceed speed x to arrive? If you interpret it as exceed speed limit then answer comes to A = 72mph. If not then 108mph. Please clarify and provide OA. Press kudos if I am right.



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Re: While driving from Corvallis to Portland, Matt obeys the speed limit.
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03 Feb 2015, 02:29
Bunuel wrote: While driving from Corvallis to Portland, Matt obeys the speed limit. Matt’s friend Vadim likes to drive faster than the speed limit and believes that he could leave well after Matt and still reach Portland first. The distance from Corvallis to Portland is 81 miles and both Matt and Vadim travel the same route at their respective constant speeds. If Matt travels at a constant speed of 36 mph and leaves 90 minutes before Vadim, what is the minimum constant speed that Vadim must exceed in order to arrive in Portland before Matt?
A. 72 mph B. 81 mph C. 96 mph D. 108 mph E. 162 mph
Kudos for a correct solution. VERITAS PREP OFFICIAL SOLUTION:Solution: D Start by determining how long it will take Matt to drive from Corvallis to Portland. D = RT, D = 81, and Matt’s R = 36, so 81 = 36T. Isolating T yields T = 81/36, or 9/4, or 2 ¼, or 2 hours and 15 minutes. This means that 90 minutes into the trip, Matt will be 45 minutes (or ¾ of an hour) from Portland. At this point we have a race: in order to beat Matt to Portland, Vadim needs to travel 81 miles in under ¾ of an hour. To find the minimum acceptable speed, return to D = RT. Vadim’s D = 81, his T = ¾, so 81 = R(¾). R = 108 and Vadim must exceed 108mph in order to arrive in Portland first.
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Re: While driving from Corvallis to Portland, Matt obeys the speed limit.
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21 Jul 2017, 05:33
Bunuel wrote: While driving from Corvallis to Portland, Matt obeys the speed limit. Matt’s friend Vadim likes to drive faster than the speed limit and believes that he could leave well after Matt and still reach Portland first. The distance from Corvallis to Portland is 81 miles and both Matt and Vadim travel the same route at their respective constant speeds. If Matt travels at a constant speed of 36 mph and leaves 90 minutes before Vadim, what is the minimum constant speed that Vadim must exceed in order to arrive in Portland before Matt?
A. 72 mph B. 81 mph C. 96 mph D. 108 mph E. 162 mph
Kudos for a correct solution. Speed of Matt = 36 mph Speed of Vadiim = v Now Matt Leaves 90 minutes before vadim. So, during this time Matt travels 36*90/60 = 54 Miles The distance left to reach Portland = 81  54 = 27 miles At this time Vadim starts travelling and he has to travel atleast 81 miles during the time Matt travels next 27 miles So, 27/81 = 36/v > v = 108 So if vadim has a speed just greater than 108 he will reach before matt.... So, vadim must exceed 108 mph in order to arrive in Portland before Matt Answer D
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Re: While driving from Corvallis to Portland, Matt obeys the speed limit.
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30 Jul 2017, 16:22
Bunuel wrote: While driving from Corvallis to Portland, Matt obeys the speed limit. Matt’s friend Vadim likes to drive faster than the speed limit and believes that he could leave well after Matt and still reach Portland first. The distance from Corvallis to Portland is 81 miles and both Matt and Vadim travel the same route at their respective constant speeds. If Matt travels at a constant speed of 36 mph and leaves 90 minutes before Vadim, what is the minimum constant speed that Vadim must exceed in order to arrive in Portland before Matt?
A. 72 mph B. 81 mph C. 96 mph D. 108 mph E. 162 mph We are given that Matt travels at a rate of 36 mph and leaves 90 minutes, or 1.5 hours, before Vadim. We can let Vadim’s time = t, so Matt’s time = t + 1.5. Since rate x time = distance, we can create the following equation and solve for t: 36(t + 1.5) = 81 36t + 54 = 81 36t = 27 t = 27/36 = ¾ So, we know Vadim must reach Portland in ¾ of an hour or less. Since rate = distance/time, his minimum speed is 81/(¾) = 81 x 4/3 = 108 mph. Answer: D
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Re: While driving from Corvallis to Portland, Matt obeys the speed limit.
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Re: While driving from Corvallis to Portland, Matt obeys the speed limit. &nbs
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