Question
A man can row at a speed of 20 km/hr in still water to a
certain upstream point and back to the starting point in a river which flows at 5 km/hr. Find his average speed for total journey.Solution
Speed of the man in still water = 20 km/hr Speed of the stream = 5 km/hr Speed downstream = (20 + 5) = 25 km/hr Speed upstream = (20 - 5) = 15 km/hr Average speed = (Speed downstream x Speed upstream)/Speed in still water = (25 x 15)/20 = 18.75 km/hr
More Boats and streams Questions
- Find the simplified value of following expression:
0.998 + 0.882 + 0.12 ?2 × 25 = 42 × 21 + 172Â
- What will come in the place of question mark (?) in the given expression?
389 + 641 - ? = 180 X 2 9 × 4 ? ÷ 16 = 144
(√1024 + √324)% of 780 = ?% of 260
What value should come in the place of (?) in the following questions.
336 ÷ 6 ÷ √16 * ? = 1400 ÷ 4
What will come in the place of question mark (?) in the given expression?
9 (? + 12) = 3 (14 + 17 - 11)
Evaluate: (768÷16)×(125÷25)−(81÷9)×12
81 ÷ 0.09 × 1.4 – 1223=?
32 × 3 (54 – 15) + 186 ÷ 3 ÷ 2 – (21)² = ?
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