two trains leave at 3pm and head 50 miles to Chicago. Train A travels twice as fast as train B and arrives 1 hour ahead. Find the speed of each train

Question

Word problems

Answer 1

d=rt

50=rt (for train B)

50=2r*(t-1) (for train A)

50=rt implies r=50/t

substitute

50=2(50/t)(t-1)

multiply both sides by t

50t=100(t-1)

50t=100t-100

50t-100t=-100

-50t=-100

50t=100

t=2 hours

50=rt

50=r*2

r=50/2

r=25 mph for train B

r=50 mph for train A