help???please??? 10 points for the best answer?

Question

This math problem....It's so complicated!!!

please, don't just tell me the answer, tell me how to do it..
I know the answer, but i don't know the way to do it.?

If an object is travieling 30 feet per second, what is its speed in miles per hour to the nearest whole number? There are 5280 feet in a mile.

so please tell me the way how to do it???

10 points to you....

Answer 1

30 ft / sec so multiply by 60 and you get how fast it is going ft / min. multiply by 60 again and you get ft/hr. sooo

108000 ft / hr. divide this by 5280 and you get mi / hr

20.45 mi / hr

Answer 2

A good general way to do this kind of thing is say

(30 ft)/(1 sec) = (30 ft)/(1 sec) * 1 * 1 * 1 = (30 ft)/(1sec) * (1 mile/5280 ft.) * (60 sec/1 min) * (60 min/ 1hour) = (30 * 1 * 60 * 60) miles/ (1 * 5280 * 1 * 1) hours.

All the other units cancel.

Just simplify the numerical part of the fraction and you're done.

Treating the names of different units as something to cancel in fractions helps you keep things straight. It's the sort of thing physicists do that doesn't quite look rigorous mathematically, but sure makes things easier and isn't exactly wrong either.

Answer 3

i think he is going about 20 miles an hour, as for how i got it, well i am terrible at math formulas and ur teacher would probably kill you for doing it this way so if u can, find the right way to do it. heres how i worked it though (i may be wrong) i divided the 5280 feet in a mile by the 30 feet he's going in a second and i got 176 seconds as how long it would take him to travel a mile. i divided that by 60 ( there are 60 seconds in a minute) to find out how many minutes it took him to travel a mile. i got 2.9 something so i roundied it to 3. it takes him 3 minutes to travel a mile and there are 60 minutes in an hour. so i divided 60 by 3 and got 20 miles an hour. I may be wrong and i am probably making it way harder than it needed to be so check with ur teacher before trusting me, thats just my best answer, hope it helps or at least gives you ideas where to start.

Answer 4

Think it through:

Goal: miles/hour


How many miles in a second (it will be a very small fraction of a mile).

How many feet in a mile? 5280
30 feet is what fraction of a mile?
=30/5280= miles/second


Now, figure out how many seconds are in an hour. 60 sec per minute, 60 min/hour,

Then, how many miles in an hour:
multiply miles/sec by the number of seconds in an hour.

Answer 5

hey dear
its quite simple
what u have to do is nothing but multiply and divide.
look 1st of all we need to convert 30 feet into mile.
since there are 5280 feet in a mile ie 5280 feet = 1 mile
theredore 30 feet = 30*1/5280
now second into hour so we'll have to multiply it by 3600 b'cause there are 3600 sec in an hour.
so the answer is 30*1*3600/5280=3600/176=20.45=20 mile/hour
after calculating answer is20 mile/hour
i hope u got it
have a nice time
bikash jain

Answer 6

First, remember: Multiply by 1 will give you the same number.
i.e 1*x = x (except when x=0)

So, multiplying by any form of 1 will also give the same result.

we want to change 30 (ft/sec) into x (miles/hr)

since 60 seconds = 1 minute
then 60*60 seconds = 60 minutes = 1 hour
the fraction (3600 seconds/ 1hour) = 1

so let's mutiply by this number:

30 (ft/second) * (3600 seconds/1hour) =
30 * (ft * 3600 seconds)/(seconds*hours) =
30 * 3600 *(ft/hour) * (seconds/seconds) =
108000 ft/hour----because seconds/seconds = 1

similarly, 1 mile = 5280 feet -----divide both sides by 5280 feet
(1 mile/ 5280 feet) = 1

Let's multiply by this fraction:

108000 (ft/hour)( 1mile/ 5280 feet) =
(108000/5280) (mile/hour) (feet/feet) =
20.455 miles/ hour

To the nearest whole number would be 20 miles/hour


Hope this helps!

Answer 7

You need to multiply by fractions that are equal on top or bottom, in order to get to the correct units. To convert from feet per second to feet per hour:

30 ft / sec * 3600 sec/ hr = 108000 ft / hr (notice that the seconds unit will cancel)

Next, to get to miles per hour

108000 ft / hr * 1 mi/ 5280 ft = 108000/5280 mi/hr = 20 mi/hr (when rounded to the nearest whole number)

Answer 8

multiply 30 times 60 then divide it by 5280

Answer 9

An object is travelling at a speed of 30feets/second.
1st we will convert 30feets/second into feets/hour.
therefore....1 hour = 60min. X 60 sec.= 3600 seconds.
then... speed in terms per hour, 3600seconds X 30feet/second = 1,08,000feets/hour.
now.... 1 mile has 5280 feets.
therefore, 108000/5280 = 20.45 miles.
tht means.... 108000 feets/hour = 20 miles/hour(rounded off) = 30feets/second.
I hope u must have got it.
Anyways have fun with maths.......... :)

Answer 10

Object travels at 30 ft / sec = 1800 ft / min

= 108,000 ft / h

= 108,000 / 5280 miles / h

= 21 mph to the nearest mph

Answer 11

30 feet / 1 second

1800 feet/ 60 seconds

108,000 feet/ 1 hour (3,600 seconds)

108,000 divided by 5280 equals 20.454545(bar)

when rounded it is 20 miles per hour