Two trains are 360 miles apart at 7 a. m. and are traveling on the same track, in opposite directions, moving toward one another. one train is traveling at 40 miles per hour and the other is traveling at 50 miles per hour. at what time will they meet?

at 4 hours after leaving, that is at 11 am

Step-by-step explanation:

1) finding the distance of the meeting point (X):

so for the train 1, the distance is "X"; for the train 2, the distance would be "360 - X"

2) replacing in the ecuation: V = X / t:

train 1: 40 miles/h = (360 - X) / t(1)

train 2: 50 miles/h = X / t(2)

⇒ from (2): t = X / 50 (3)

replacing (3) in (1):

⇒ 40 = (360 - X) / ( X / 50)

⇒ 40 = (50 * (360 -X)) / X

⇒ 40X = 18000 - 50X

⇒ 90X = 18000

⇒X = 18000 / 90 = 200 miles  meeting distance  (4)

replacing (4) in (2):

⇒50millas/h = (200miles) / t

⇒ t = 200miles / 50 miles/h

⇒ t = 4h

not only in mathematics, scientific proof also are required in the other field of science. also maths proofs are of particular structure, containing steps and logics. so proving is like doing science, it is science. that's why it is important to prove. 

an inaccurate proof leads to errors, or stating results that are not accurate.  which wil mess the probelm up you dont want this