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unknown08
Mar 12, 2008, 01:23 PM
I have no clue how to solve these 2 word problems!
1. Chris cuts half a rectangular lawn 40m by 30m, by mowing strips of equal width around the perimeter. Jeri cuts the small rectangle that's left. How wide a strip does Chris cut so that they share the work equally?

2. Dieter makes a journey of 430km travelling 160km by bus and 270 km by car. If the car averages 10km/h faster then the bus and the whole trip takes 5 hours, what is the speed of the car?

ISneezeFunny
Mar 12, 2008, 01:26 PM
First give it a try. Then we'll help along the way.

galactus
Mar 12, 2008, 03:29 PM
I have no clue how to solve these 2 word problems!
1. Chris cuts half a rectangular lawn 40m by 30m, by mowing strips of equal width around the perimeter. Jeri cuts the small rectangle that's left. How wide a strip does Chris cut so that they share the work equally?


The area of the entire lawn is 1200 square meters. Right?

Since they're equal, the inside rectangle has area 600 and the portion Chris cuts is also 600.

Then let the width of the swath that Chris cuts be x.

Now, draw a picture and try to set up the equation. Give it a go and let us know what you get.



Dieter makes a journey of 430km travelling 160km by bus and 270 km by car. If the car averages 10km/h faster then the bus and the whole trip takes 5 hours, what is the speed of the car?


Since d=rt, t=d/r. We can construct an equation using the givens, distance and rate.

Since the bus's speed is r, then the car must be 10+r.

The sum of the two must equal 5.

Give it a go and let us know what you come up with.

helpingu
Dec 13, 2009, 06:28 PM
The response above is great! Props to you man, I've worked it out and the one above deserves Good Thing!