Out of a distance of 360 km if 240 km is covered by bus and rest by train it takes 8 hr to complete the journey however if 120 km are travelled by bus and rest by trian it takes 1 hr less what is the speed of train and bus
Answers
∴, according to the question,
240/x+120/y=8 -------------(1)
120/x+240/y=7 -------------(2)
Multiplying (1) with 1 and (2) with 2 and subtracting we get,
240/x+120/y=8
240/x+480/y=14
∴, -360/y=-6
or, 1/y=6/360
or, 1/y=1/60
or, y=60
∴, 120/x=7-240/y
or, 120/x=7-240/60
or, 120/x=7-4
or, 120/x=3
or, 1/x=3/120
or, 1/x=1/40
or, x=40
∴, Speed of the bus is 40km/hr and speedof the train is 60km/hr.
Answer:
Step-by-step explanation:
let
speed of train be y and that of bus be x
first equation = 240/x + 120/y = 8 ( time = distance / speed )
second equation = 120/x + 240/y = 7 ( " )
take 1/x as 'u' and 1/y as 'v'
(1) 240u + 120v = 8
120u + 60v = 4 ( dividing by 2 )
(2) 120u + 240v = 7
by elimination 180v=3
v= 1/60
substituting the value to equation 1
120u + 60/60 = 3
120u = 3
u = 1/40
therefore v= 1/60 = 1/y
y = 60
u= 1/40 = 1/x
x = 40
speed of train = 60
speed of bus = 40