Distance problem: Driver A heasds toward Driver B at a speed

[mentoce]

"Driver A heasds toward Driver B at a speed of 30 mph. Driver B is 130 mi away and heads toward Driver A travelling 40 mph. If Driver B starts the journey 15 minutes after Driver A then how long will it take the trucks to meet?"

What I'm having trouble with is how to set up the problem. thanks for any help.

 

[galactus]

distance = (rate)(time).

Driver A = 30t

Driver B leaves 15 minutes later. Remember, consistent units.

15 minutes = 1/4 hour.

40(t-1/4)


The total distance is 130 miles.

 

[mentoce]

right, but where do you go from there?

 

[stapel]

Take the two distance expressions the tutor gave, together with the distance value the exercise gave you, and figure out the relationship. (Drawing a picture might help.) Create the equation, and solve it.

What are your thoughts? What have you tried? Where are you stuck? Please be specific. Thank you.

Eliz.

 

[mentoce]

ive been doing that for a very long time, what i wanted was just somwone to set up the problem for,but now its too late. oh well

 

[tkhunny]

Setting up the problem is the part you are supposed to be learning!

 

[galactus]

I done everything but give you the answer. Set it up.

The two trucks must travel 130 miles between them.

Distance=(rate)(time)

\(\displaystyle \L\\\underbrace{30t}_{\text{car A\\(rate)(time)}}+\underbrace{40(t-1/4)}_{\text{car B\\(rate)(time)}}=\underbrace{130}_{\text{distance}}\), solve for t.