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If an object travels 100 feet in 2 seconds, what is the
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21 Oct 2010, 18:42
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If an object travels 100 feet in 2 seconds, what is the object’s approximate speed in miles per hour? (Note: 1 mile = 5280 feet) A. 3.4 B. 3.8 C. 34 D. 38 E. 340
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Re: conversion
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22 Oct 2010, 05:02
Conversion questions are best dealt using a one step approach. Let me illustrate: Let's say we want to convert a speed of 100 miles/hour to feet/sec. Speed = 100 miles/1 hour = (100 x 5280 feet)/(1 x 3600 sec)= 146.67 feet/sec So, simply convert the units to what you want along with the conversion factor. Let's take your question now. If an object travels 100 feet in 2 seconds, what is the object’s approximate speed in miles per hour? (Note: 1 mile = 5280 feet) Speed = 100 feet/2 sec = (100×1/5280 miles)/(2×1/3600 hour) = 5x3600 miles/528 hr = 34 miles/hr Note: Since 1 mile = 5280 feet, hence here to convert we say 1 foot = 1/5280 miles.
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Re: conversion
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21 Oct 2010, 19:01
shrive555 wrote: If an object travels 100 feet in 2 seconds, what is the object’s approximate speed in miles per hour? (Note: 1 mile = 5280 feet) 3.4 3.8 34 38 340 i always mess such conversion questions. \(100\) feet in 2 seconds; \(100*\frac{3,600}{2}=50*3,600\) feet in 1 hour; \(\frac{50*3,600}{5,280}\approx{34}\) miles in 1 hour. Answer: C.
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Re: conversion
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22 Oct 2010, 05:55
Bunuel wrote: shrive555 wrote: If an object travels 100 feet in 2 seconds, what is the object’s approximate speed in miles per hour? (Note: 1 mile = 5280 feet) 3.4 3.8 34 38 340 i always mess such conversion questions. \(100\) feet in 2 seconds; \(100*\frac{3,600}{2}=50*3,600\) feet in 1 hour; \(\frac{50*3,600}{5,280}\approx{34}\) miles in 1 hour. Answer: C. thanks for your better explanation......



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Re: If an object travels 100 feet in 2 seconds, what is the object's appro
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13 May 2011, 08:46
1 mile = 5280 feet => 1 feet = 1/5280 miles If the object ravels 100 feet in 2 sec then it travels 100/2 * 60 * 60 feet in 1 hour (1 hr = 60 min * 60 sec) = 3600 * 50 feet in 1 hour = 180000 feet in 1 hr = 180000/5280 miles in 1 hour = 18000/528 miles/hr ~ 34 miles/hr Answer  C
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Re: If an object travels 100 feet in 2 seconds, what is the object's appro
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13 May 2011, 08:49
In 2 seconds 100feet In 1 second50feet In 3600 seconds(1hour=3600sec)3600*5feet. Now 5280 feet = 1 miles so, 3600*5 feet= 3600*5/5280. Now use approximation.. (36*5)/5280 * 100 = 180/5280 *100 or 18/5280 * 1000= 3/88 *1000. Now 3/90= 1/30= .03 So 3/88*1000 ~ .03*1000=33.3~34. Idea is to not multiply anything until last few steps when you can use approximation better.
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Re: If an object travels 100 feet in 2 seconds, what is the object's appro
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13 May 2011, 11:32
speed= 100 feet/2 sec = 50 feet /1 sec = 50*60*60 feet / hours
Now divide the entire distance traveled into number of miles
it gives 18000/5280
~35 Hence choice c



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Re: conversion
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08 Jul 2012, 10:50
100 (feet)/2 (sec) *1 (mile)/5280 (feet)* 3600 (sec)/1 (hour) > cancel out (feet) and (sec) and you will get
(100*3600)/(2*5280) = 34.09



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Re: If an object travels 100 feet in 2 seconds, what is the
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19 Jul 2012, 04:25
1 mile = 5280 feet => 1 feet = 1/5280 mile 1 hr = 3600s => 1s = 1/3600 hr If an object travels 100 feet in 2 seconds => speed = 100/2 feet/s = 50 feet/s = 50 *(1/5280) / (1 *(1/3600)) miles/hr = 3600 * 50 / (5280) miles/hr = 18000/ 528 miles/hr ~ 18000/525 = 180 * 4/ 21 miles/hr = 240/7 miles/hr ~ 34miles/hr So, Answer is C(34) Hope it helps!
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Re: conversion
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17 Oct 2013, 04:37
Bunuel wrote: shrive555 wrote: If an object travels 100 feet in 2 seconds, what is the object’s approximate speed in miles per hour? (Note: 1 mile = 5280 feet) 3.4 3.8 34 38 340 i always mess such conversion questions. \(100\) feet in 2 seconds; \(100*\frac{3,600}{2}=50*3,600\) feet in 1 hour; \(\frac{50*3,600}{5,280}\approx{34}\) miles in 1 hour. Answer: C. Thanks! nice explanation! helped me understand.



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Re: conversion
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17 Oct 2013, 04:42



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Re: If an object travels 100 feet in 2 seconds, what is the
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20 Sep 2014, 09:05
shrive555 wrote: If an object travels 100 feet in 2 seconds, what is the object’s approximate speed in miles per hour? (Note: 1 mile = 5280 feet)
A. 3.4 B. 3.8 C. 34 D. 38 E. 340 My approach is as follows: 100 feet in 2 Secs. Therefore 50 feet in 1 Sec 50 X 60 =3000 Feet in 1 Min And 3000 X 60 = 180000 Feet in 1 Hour Now Conversion..... 180000/5280~=180000/5000=36 The answer should be slightly less than 36.That is C.



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Re: If an object travels 100 feet in 2 seconds, what is the
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26 Jul 2015, 16:53
Bunuel wrote: shrive555 wrote: If an object travels 100 feet in 2 seconds, what is the object’s approximate speed in miles per hour? (Note: 1 mile = 5280 feet)
\(\frac{50*3,600}{5,280}\approx{34}\) miles in 1 hour. Answer: C. How do you do that math fast and not screw it up? That's what I screwed up on this problem.



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Re: If an object travels 100 feet in 2 seconds, what is the
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26 Jul 2015, 16:58
gmatser1 wrote: Bunuel wrote: shrive555 wrote: If an object travels 100 feet in 2 seconds, what is the object’s approximate speed in miles per hour? (Note: 1 mile = 5280 feet)
\(\frac{50*3,600}{5,280}\approx{34}\) miles in 1 hour. Answer: C. How do you do that math fast and not screw it up? That's what I screwed up on this problem. You can use approximation as the given options are spread far and wide Lets take the example of this question: \(\frac{50*3,600}{5,280}\) Recognize here that 36 = 18*2 and 54 = 18*3. 5280 is almost equal to 5400. Thus you can cancel out 3600 and 5280 to get 2/3 (approx.). For approximations of fractions, you need to a bit imaginative to cancel out the maximum you can. Now the given equation reduces to 50*2/3 = 100/3 = 33.33333 which is very close to 34. Hope this helps.



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Re: If an object travels 100 feet in 2 seconds, what is the
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03 Apr 2016, 10:34
shrive555 wrote: If an object travels 100 feet in 2 seconds, what is the object’s approximate speed in miles per hour? (Note: 1 mile = 5280 feet)
A. 3.4 B. 3.8 C. 34 D. 38 E. 340 my approach 100ft/2sec = 50ft/sec or 3000ft/min, or 180,000/hour now..1 mile is 5280 180,000/5000 = 36 so clearly is less than 36, but smth around 30 only option C



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Re: If an object travels 100 feet in 2 seconds, what is the
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19 Nov 2016, 17:31
difficult question. I get to the below with some work
50 *3,600/ 5,280
then I decided to approximate = 18,000/5,000 = 36.
at this point I had to decide between 34 and 38. That was the difficult part of me.



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Re: If an object travels 100 feet in 2 seconds, what is the
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09 Feb 2018, 22:45
100 feet per 2 seconds , which translates to 3000 ft per minute.
Speed for 1 hour = (3000 * 60) / 5280 = ~ 34
Ans: C



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Re: If an object travels 100 feet in 2 seconds, what is the
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19 Apr 2018, 04:52
1) First change 100ft/2seconds to 50ft/1second. 2) Convert feet to miles = 50 * 1 / 5280 = 50/5280 3) Convert seconds to hours = 1 / (60)^2 = 4) Divide – multiply reciprocal = (60)^2*50/5280. 5) 3600*50=180000/5280. 6) By looking at this fraction we conclude that it needs to be multiplied by at least 30.
Thus therefore 34. Multiplying times 8 would be make the number too large



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If an object travels 100 feet in 2 seconds, what is the
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15 Aug 2018, 05:22
Bunuel wrote: shrive555 wrote: If an object travels 100 feet in 2 seconds, what is the object’s approximate speed in miles per hour? (Note: 1 mile = 5280 feet) 3.4 3.8 34 38 340 i always mess such conversion questions. \(100\) feet in 2 seconds; \(100*\frac{3,600}{2}=50*3,600\) feet in 1 hour; \(\frac{50*3,600}{5,280}\approx{34}\) miles in 1 hour. Answer: C. Dear Bunuel, How would you approach this last division: \(\frac{50*3,600}{5,280}\approx{34}\)?
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If an object travels 100 feet in 2 seconds, what is the
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24 Jul 2019, 17:09
shrive555 wrote: If an object travels 100 feet in 2 seconds, what is the object’s approximate speed in miles per hour? (Note: 1 mile = 5280 feet)
A. 3.4 B. 3.8 C. 34 D. 38 E. 340 Answers are very spread out, also notice the numbers A) 3.4 and B) 3.8 are identical to C) 34 and D) 38 except for a power of 10 and E) is identical to A) and C) except with another extra power of 10. After converting we get (50*60^2)/(5280) so quickly rounding down denominator to 5000 gives us 36 while rounding up to 6000 gives us 30 so the answer should be around the average of those, C) 34 is the only choice since D is higher than the rounded up total.




If an object travels 100 feet in 2 seconds, what is the
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