Question

Question 15 answer please . It's urgent.

Answer 1

Hi !

Case I : When they travel in same direction

Speed of car starting from A = x km/hr
Time taken = 15 hrs
Distance travelled by A  = speed x time = 15x metres

Speed of car starting from B = y km/hr
Time taken = 15 hrs
Distance travelled by B  = speed x time = 15y metres

If they travel in same direction and reach  in same time , they reach at a point C
                    [ A picture is attached , refer to the pic 1 ]
We know that AB = 150 km
also , 
AC = 15x metres [ distance traveled by A ]
BC = 15y metres [ distance traveled by B]

AB = AC - BC
150 = 15x - 15y

15x - 15y = 150

x - y = 10             -----> (1)

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Case II : When they move in opposite directions :-

Speed of car A = x km/hr
Time taken = 1 hr
Distance = x metres

Speed of car B = y km/hr
Time taken = 1 hr
Distance = y metres

If they travel in opposite directions , they meet at a point C , between A and B [ refer to the pic 2 ]

x + y = 150             -----> (2)

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Solving equations 1 and 2 , we get 



x - y = 10
x + y = 150
----------

2x = 160

x = 80

x - y = 10

y = 70

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Speed of car starting from A = 80 km/hr
Speed of car starting from B = 70 km/hr


Hope it helped !