# 2½ inches per minute, 240 inches per hour, 1/4 foot per minute; which is fastest?

hala718 | High School Teacher | (Level 1) Educator Emeritus

Posted on

2 1/2 inch per min.

240 inch per hour

1/4 foot per min.

Which is faster?

First we need to convert all of the above to the same unit.

We will convert to inch per min.

So we have:

2 1/2 inch/ min

Now we will convert 240 inch / hour

We know that 1 hour = 60 m.

==> 240 inch / hour = 240 inch / 60 min = (240/60) inch/ min.

==> 240 inch / hour = 4 inch / m

Now we will convert 1/4 foot/ min

We know that:

1 ft = 12 inch

==> 1/4 ft = 12/4 inch

==> 1/4 ft = 3 inch.

==> (1/4) ft / min = 3 inch/ min

Now we will compare:

2/12  < 3 < 4

==> 2 1/2 ich/min <  1/4 ft/min <  240 inch/ hour

neela | High School Teacher | (Level 3) Valedictorian

Posted on

We convert all the three given speeds in feet per hour and then we see which is fastest.

1)

1 foot = 12 inch

1 hour = 60 minute:

2and1/2 inches per minute:

2and 1/2 inch = 5/2 inches = (5/2)/12 foot = 5/24 foot.

Therefore 2 and 1/2 inch per minute = (5/24)60 ft /h = 12.5 ft.

2)

240 inches per hour = 240/12 ft/h = 20 ft.

3)

1/4  ft/m   =  (1/4)60 ft /h = 15 ft/h.

Comparing the three speeds in ft/h, 240inch/hour =  20 ft/h is fastest .