SOLUTION: John started walking East at 10:00 AM at a rate of 2 km/hr. James stated walking South at 10:30 AM at a rate of 4km/hr. What time is it when they are 5 km apart?

Algebra.Com
Question 596745: John started walking East at 10:00 AM at a rate of 2 km/hr. James stated walking South at 10:30 AM at a rate of 4km/hr. What time is it when they are 5 km apart?
D (x) = Rate x time



Tried formula below, but stuck on time part????
a2 + b2 = c2 so 4x2 + 2x2 = 25
x= 1.25




Answer by solver91311(24713)   (Show Source): You can put this solution on YOUR website!


At 10:30 when James starts, John will be 30 minutes into his trip. 30 minutes at 2 km/hr is 1 km. One hour later John will be 3 km from the start and James will be 4 km from the start, making a 3-4-5 right triangle at time 11:30.

That was the easy way. Now the hard way:

In the first 30 minutes John goes 1 km. Every hour after that, he goes 2 km. So counting hours since JAMES starts, John goes km. James is going twice as fast as John, so every hour after James starts he goes km.

In order for them to be 5 km apart:



Simplifying:



Solve for the . Toss out the negative value (you don't care what happened before either of them started the trip, do you?)

John

My calculator said it, I believe it, that settles it
The Out Campaign: Scarlet Letter of Atheism


RELATED QUESTIONS

at 3:00pm, andy began walking directly south from point A at a rate of 4mi/hr. at the... (answered by Alan3354)
A started walking in north at 7 am with the speed of 5 km/hr. after one hour B started... (answered by ankor@dixie-net.com)
Pls help me with my homework. I am confused in converting miles and km. Two men are 10... (answered by Alan3354)
two- way radio range two children own two-way radios that have a maximum range of 2... (answered by xcentaur)
two- way radio range two children own two-way radios that have a maximum range of 2... (answered by xcentaur)
A salesman started walking from office A at 8:30 AM. at the rate of 2.50 kph. He arrived... (answered by ankor@dixie-net.com,ikleyn)
Two surveyors with two-way radios leave the same point at 9:00 AM, one walking due south... (answered by mananth)
At 10am a plane leaving an airport traveling east at 400 mi/hr and another plane located... (answered by Fombitz)
Two children own two-way radios that have a maximum range of 4 miles. One leaves a... (answered by jorel1380)