many american cars feture speedometers that show kilometers per hour. If you are required to drive 55 miles and you know that one kilometer is approximately 5/8 of a mile, how many kilometers would you cover in that journey? 800 but how and why?
nevermind. I just got it right now. 5/8 * 1/100 right? =800
Settin up simple ratios is often the best way to solve these kind of problems
5 miles = 8 km
so 55 miles = x km
5/55 = 8/x
5x=440
x=88 km
(800 km is clearly a ridiculous answer)
You can set up a proportion like this, with x representing the kilometers:
5 / 8 = 55 / x
As you see, it's a much smaller number than 800.
but that the answer on my math book. the choices are 625,800,850,1000. my math book is not wrong
why 55? i don't get it?
sorry i meant 500 miles
OK. 500 miles = 800 kilometers
Thank you for using the Jiskha Homework Help Forum. You might like to save the following link with conversions. Just enter 55 miles and see what you get!
http://www.allchin.net/converter/basicmulti.html
3 answers