Thread: Chewing Gum and Miles ?

What answer did you get and how did you get it?

I just multiplied 30 mil by 3.5 which =105 million inches and knew there were 63, 360 inches in a mile and went from there by dividing 63,360 by 105 million.

I'm sure there is a shorter way ..correct ?

My answer was 1657.196 miles.

Originally Posted by Bluerain

and went from there by dividing 63,360 by 105 million.

The other way around.

Originally Posted by Bluerain

I'm sure there is a shorter way ..correct ?

No, that's pretty much how it should be done.

Originally Posted by Bluerain

My answer was 1657.196 miles.

I agree, except that the last digit should be 7 due to rounding (since the following digit is 9 in my calculation). If the first thrown away digit is >= 5, the last remaining digit is increased by 1.

Originally Posted by Bluerain

I just multiplied 30 mil by 3.5 which =105 million inches and knew there were 63, 360 inches in a mile and went from there by dividing 63,360 by 105 million.

I'm sure there is a shorter way ..correct ?

My answer was 1657.196 miles.

Nope, that's the quickest way to do it.

For notation's sake I will write



Note that all the units except miles cancel. This is the basis of unit analysis and I find it the easiest way of figuring out whether to multiply or divide when converting units (I usually work in metric myself)

After a bit of simplifcation of both units and numbers we get


(IMO the nearest integer is close enough for rounding purposes unless the question says something else)