Andrew M. answered • 01/21/17
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Hello Lexi.
To convert miles/hour (mph) to feet/second (fps), consider that 1 mile = 5280 feet and 1 hour = 3600 seconds.
1 mph = (1 mile)/(1 hour) = (5280 feet)/(3600 seconds) = 1.47 feet/second.
You can also use the data given:
(11 fps)/(7.5 mph) = 1.47
(66 fps)/(45 mph) = 1.47.
Andrew M.
I am not sure I understand your question, Lexi. Perhaps you are asking how to convert units in general?
Let's say you want to convert 7.5 miles/hour to feet per second. Here is one way to do the conversion:
7.5 (miles/hour) * 5280 (feet/mile) * (1 hour)/(3600 seconds) = 11 feet/second.
Notice how the units miles and hours cancel out (numerator/denominator)?
You can use a similar strategy to convert any units. For example, let's say you want to convert 40 gallons/minute to liter/second. 1 gallon = 3.8 liters and 1 minute = 60 seconds, so:
40 gallons/minute = 40 (gallons/minute) * 3.8 (liters/gallon) * (1 minute)/(60 seconds) = 2.5 liters/second.
Does this help?
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01/21/17
Lexi R.
I will give you the exact question I would like to be answered because I do not think we are on the same page right now.
"A person running 7.5 mph is going 11 ft per second. A cheetah running at 45 mph is going 66 ft per second. The ratio of feet per second to mph in each case is which of the following? A) 15/22 B) 5/6 C) 22/15 D) 3/2"
I need help figuring out the equation for this problem. I do not know how to get to the right answer.
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01/21/17
Andrew M.
I see. If you think carefully, that was the first thing I answered, except I also gave you a decimal answer rounded to the nearest hundredths: 1.47.
In fractions, it is just 5280/3600 which simplifies to 22/15.
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01/21/17
Lexi R.
Oh, I am very sorry that I could not see that from the beginning. I am very much obliged to you for taking this time to help me.
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01/21/17
Andrew M.
You’re welcome. Good luck with your studies.
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01/21/17
Lexi R.
01/21/17