Question

Two trains leave from the same station at the same time and travel in opposite directions. One train
travels at an average rate of 50 mph, the other at 70 mph. In how many hours will they be 330 miles
apart? State what x represents, state the equation, and then state the answer.

Answer 1

Answer:

speed=distance/time

let x=distance

let v=speed

let t=time

For train(1)

x(1)=v(1)t

or,

x(1)=18*t

For train(2)

x(2)=v(2)t

or

x(2)=12*t

When the distance between the two is 246 miles, it means

x(1)+x(2)=246 miles

So

246 = 12*t+18*t

246=30*t

or,

t=8.2 hours.

Step-by-step explanation:

So: RT=D. Solve this for T, since that's our unknown. You get T=D/R. Substitute R=30 and D=246.

T = 246/30; T=8.2 hours   If they want it in hours and minutes, it's 8 hours and 12 minutes.

Train I 70 mph

Train II 80 mph

They are moving in opposite directions

so effective speed = 150 mph

Distance = 210 miles

Time = distance/speed

Time = 210 / 150

Time = 1.4 hours

Time they will be 210 miles apart 1 hour 24 minutes

i hope this helps

Answer 2

Answer:

210

Step-by-step explanation: