# Fifty Plus (50+) - Math Challenged...

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View Full Version : Math Challenged...

LastPlace
06-16-05, 10:37 PM
There is a saying that if you remember the '70s you were not there and one of the many things I don't remember is math. Since my computer doesn't average speed does anybody have a formula that lets me enter milage and time to get an average or does anyone know where I can find a chart.

For example, Tuesday we did 20 miles in 1hr, 36 minutes and today we did the same 20 miles in 1hr and 15 minutes. How does an aged brain do the math?

LastPlace

Digital Gee
06-16-05, 11:12 PM
The first time, you rode an average of 12.5 mph. The second, you rode an average of 16. In the first instance, you rode 1.6 hours (36 minutes = .6 of an hour), and in the second run, you rode 1.25 hours. Divide both by 20 miles and you'll get these results.

And avoid appearing on NPR's Whatdya Know, with Michael Feldman, because you will get the question wrong if the category is Things You Should Have Learned in School. :-)

Longhorn
06-16-05, 11:21 PM
The formula is Distance = Rate*Time. So you can divide the distance by the time (in hours, since you want miles per hour) to solve for the rate.

(Just a generalization of the calculators that Digital Gee did for you. I teach math so I couldn't resist. :D)

JavaMan
06-16-05, 11:37 PM
This spreadsheet may be easier for you to use.

RonH
06-17-05, 06:53 AM
Example: time = 2 hours and 17 minutes. distance = 38.6 miles

First convert the hours (2 hours) to minutes by multiplying them by --> 60. 2x60=120

Then add the minutes (17 minutes) to that number. --> 120+17=137

Now divide by 60 to get the decimal equivalent. --> 137/60=2.283

Now divide the miles (38.6 miles) by the time (2.283). --> 38.6/2.283=16.9 mph

LastPlace
06-17-05, 01:10 PM
Thanks folks. It's all coming back to me.....at least I think so.

LastPlace

Garfield Cat
06-19-05, 09:54 AM
The easiest thing to do is to buy a new cyclometer. They're relatively inexpensive for the low end models and you should be able to get the average speed feature with it. Today is Father's day and maybe you'll get one today. If not, whatever you get, exchange it for a new cyclometer.

LastPlace
06-26-05, 10:05 PM
Garfield,
Thanks for the reply. I have had a basic Sigma for the last year but it did not have an
average speed function. Last night I put on my TOPEAK Panoram V12 and so far so good,
and yes it does have an average speed function. Eighteen miles at 11.8 mph. Nice easy
ride.

LastPlace

chroot
07-02-05, 03:18 AM
Let me introduce you to the google calculator, which is perfect for doing math with various units. If you want to know your average speed, go to www.google.com and type in "20 miles / 96 minutes in mph" and hit enter. Click this link to see what it looks like:

- Warren

jjj606
07-02-05, 07:35 PM
Yes, google calculator is the way to go.
"20 miles / 1 hour 36 minutes in mph" also works.
"15 mph in feet per second" = 22 feet per second
"1 3/8 inches in mm" = 34.925 mm

LastPlace
07-02-05, 09:44 PM
Thanks for the help. I bought a Panoram v12 and it does all the math for me, i.e.
it averages speed but thanks again.

LastPlace