Aboat travelled 231 km downstream and back. the trip downstream took 11 hours. the trip back took 77 hours. find the speed of the boat in still water and the speed of the current

Speed of boat in still water is 12 km/hr and speed of current is 9 km/hr

Solution:

From given,

Downstream distance = 213 km

Time taken for downstream = 11 hours

Thus, speed is given as:

Thus downstream speed is 21 km/hr

Also,

Upstream distance = 213 km

Time taken for upstream = 77 hours

Thus, speed is given as:

Thus upstream speed is 3 km/hr

If the speed downstream is "a" km/hr and the speed upstream is "b" km/hr , then:

Here, a = 21 and b = 3

Therefore,

Thus speed of boat in still water is 12 km/hr and speed of current is 9 km/hr

1. 3.4/4

2. 0.8/7

3. 0.5 x 3

4. 0.9 x 6

5. 10.8

6. 2.35

7. 0.567

8. 9.35

9. 0.02

10. 0.06

11. 0.16

12. 0.42

13. 0.63

14. 5.6

15. 8.1

16. 9.9

17. 0.28

18. 0.48

19. 0.27

20. 0.49

21. 0.45

22. 0.72

23. 0.9

24. 0.88

25. 0.75

26. 0.16

27. 0.328

28. 0.495

29. 0.72

30. 1.068