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Q:
A) 9 and 3 kmph | B) 6 and 7 kmph |
C) 8 and 1 kmph | D) 7 and 2 kmph |
Answer: C) 8 and 1 kmph
Explanation:
Explanation:
Downstream speed = 72km/8hrs = 9 kmph
upstream speed = 84km/12hrs = 7 kmph
speed of boat = avg of downstream and upstream speeds
speed of boat = (9+7)/2kmph = 8 kmph.
current speed = half of the difference of downstream and upstream speeds
currend speed = (9-7)/2kmph = 1 kmph