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Two trains leave the same station at the same time, but are headed in opposite directions. One train travels at 70 mph and the other train travels at 80 mph.

How much times passes until the trains are 600 mi apart?

Enter your answer in the box

___hours

User EmmanuelB
by
8.1k points

2 Answers

7 votes
4 hours til the trains are 600 miles apart
User Jason Stein
by
8.2k points
2 votes

Let

x--------> the time in hours

y-------> the distance in miles

we know that

The speed is equal to


Speed=(distance)/(time)

in this problem


Speed=(y)/(x)


y=(Speed)*x

Equation First Train


y1=70x

Equation Second Train


y2=80x


y1+y2=600\ miles ---------> equation
1

Substitute the values of
y1 and
y2 in the equation
1


70x+80x=600

Solve for x


150x=600


x=4\ hours

therefore

the answer is


4\ hours

User Raja Manickam
by
9.2k points