# word problem!!! need immediate helpp! pleasse??

• Jan 18th 2009, 05:30 PM
annabananzaa
word problem; distance
two cars leave from the same place and travel in opposite directions. one car travels 30 mph fgaster than the other. after 2.5 hours, they are 265 miles apart. what are the rates of the two cars?

ive tried but i cant seem to come up with an equation. once i have the equation, i will be able to figure it out. ive always had a hard time interpreting word problems. any help at all is appreciated.

thank youu!
• Jan 18th 2009, 07:06 PM
star_tenshi
Car A:
Let the speed of car A be x mph, thus in 2.5 hours, the distance travelled by car A in 2.5 hours would be (x mph) x (2.5 h) = 2.5x (notice how the units cancel out, miles/hr x hr = miles)

Car B:
Say we let car B be the faster car, and so it will have a speed 30 mph faster than car A, so it's speed has to be 30+x mph. Hence the distance it travelled in 2.5 hours would be (30+x mph) x (2.5 h) = 2.5(30+x) (again, the units cancel out to miles)

We know that after two hours, the cars are 265 miles apart. Since they travelled in opposite directions, we can assume that the distance they travelled is in a straight line from one another. So the resulting equation should be:

Distance travelled by car A + distance travelled by car B = 265 miles

Then solve for x, which is the speed (rate) of car A, then substitute and find the speed for car B.

Hope this helps!
• Jan 18th 2009, 07:27 PM
annabananzaa
yess! it did help!

it was probably so simple to you. lol.
• Jan 18th 2009, 07:47 PM
annabananzaa
ok, i understand the equation at the end, im just having a difficult time figuring out what you meant by eqation you gave for car A??

how wouldi go about solving that. maybe its just the wording im having difficulty with.....
• Jan 18th 2009, 08:03 PM
star_tenshi
Distance travelled by car A + distance travelled by car B = 265 miles
2.5x + 2.5 (30 + x) = 265

The above equation is from the results in purple from my previous post. Then solve for x, which is the speed of car A.
• Jan 18th 2009, 08:50 PM
annabananzaa
ooohh! i get what you were doing now. lol. that was careless on my part.
thankk you for clarifying that for me!
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