|
Question 107174: Can you help me formulate an equation for the following homework problem? It did not come from a book. Thanks
Two friends live 15 miles apart. One day, they decide to jog and meet each other. Tanya leaves her house and heads east, jogging at a rate of 2.5 mph. At the same time Kelly leaves her house and heads west, jogging at 3.5 mph. How long does it take for the two to meet?
15= 2.5x for Tanya and
15= 3.5 x for Kelly? This can't be right, as I can only have one x. Please help
Found 2 solutions by checkley75, stanbon:
Answer by checkley75(3666)   (Show Source):
You can put this solution on YOUR website! Distance=rate*time or time=distance/rate & seeing as the rates are accumulative, we have:
15/(2.5+3.5)=x now cross multiply.
6x=15
x=2.5 hours for them to meet.
Proof
2.5*2.5+3.5*2.5=15
6.25+8.75=15
15=15
Answer by stanbon(75887) (Show Source):
You can put this solution on YOUR website! Two friends live 15 miles apart. One day, they decide to jog and meet each other. Tanya leaves her house and heads east, jogging at a rate of 2.5 mph. At the same time Kelly leaves her house and heads west, jogging at 3.5 mph. How long does it take for the two to meet?
------------------------
They are jogging toward one another so neither needs to jog 15 miles.
---------------------
Tanya DATA:
Rate = 2.5 mph; distance = x miles; time = d/r = x/2.5 hrs
----------------
Kelly DATA:
Rate = 3.5 mph; distance = "15-x" miles ; time = (15-x)/3.5 hrs
-------------------------
Tanya time = Kelly time
x/2.5 = (15-x)/3.5
3.5x = 37.5-2.5x
6x = 37.5
x = 6.25 miles
----------------
Tanya time = x/2.5 = 6.25/2.5 = 2.5 hrs
--------------
Kelly time = (15-x)/3.5 = 8.75/3.5 = 2.5 hrs
===================
Cheers,
Stan H.
|
|
|
| |
