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the distance between two towns is 300km . two cars start simultaneously from these towns and move toward each other . the speed of one car is more than other by 7km/hr . if the distance between the cars after 2hrs is 34km find the speed of cars |
Answer» Given data :-
Solution :-Let, first car be A and second car be B Let, speed of car B = x KM/hr .....( 1 ) Hence, according to given {The Speed of one car is more than other by 7 km/hr.} → Speed of A = {x + 7} km/hr .....( 2 ) The distance between the cars after 2hrs is 34 km. hence, → Total distance travel by A and B before 2 hour = {300 - 34 } km → Total distance travel by A and B before 2 hour = 266 km .....( 3 ) → Total time taken by A and B to cover 293 km = 2 hour .....( 4 ) Now, we use formula of relative speed → Relative speed of A and B = {Total speed}/{Total time} [from ( 1 ), ( 2 ), ( 3 ) & ( 4 )] → x + x + 14 = 266/2 → 2x + 7 = 133 → 2x = 133 - 7 → 2x = 126 → x = 126/2 → x = 63 km/hr Hence, speed of B is 63 km/hr. Put VALUE of x in eq. ( 2 ) → Speed of A = x + 7 → Speed of A = 63 + 7 → Speed of A = 70 km/hr Hence, speed of A is 70 km/hr. Hence, speed of A and B is 70 km/hr and 63 km/hr respectively. |
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