DS question

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DS question

by bww » Sat May 12, 2007 2:20 pm
On a certain day it took Bill three times as long to drive from home to work as it took Sue to drive from home to work. How many kilometers did Bill drive from home to work?

(1) Sue drove 10 kilometers from home to work, and the ratio of distance driven from home to work time to drive from home to work was the same for Bill and Sue that day.
(2) The ratio of distance driven from home to work time to drive from home to work for Sue that day was 64 kilometers per hour.
For one reason or another, I'm having a really hard time understanding what "ratio of distance driven from home to work time to drive from home to work" means. I'm guessing this: It takes Sue t minutes to drive 10 km from home to work, so for Bill this is d/3t? Set 10/t=d/3t? Can't be that easy, is it? The word "time" after "home to work" is really throwing me off?

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by Neo2000 » Wed May 16, 2007 8:43 pm
I am not sure the second statement is correct. Ratios do not have any units.

Ratios are defined as comparison of two or more numbers having the same units for e.g when finding ratio of speeds, if one speed is in Km/hr then the other also has to be in terms of km/hr

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by aim-wsc » Wed May 16, 2007 9:08 pm
I cannot explain it in detail due to the limited resources I've. :(

by point 1. you can say that it took both bill and sou same amount of time to reach to office from their respective homes.
by point 2. you get the speed of sou.

What's the source? the question is badly constructed btw not recommended for study.

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by Cybermusings » Wed May 16, 2007 11:33 pm
Are you sure the question is worded correctly?