Question

What is the speed of the boat in still water? 

 I. The boat covers a distance of 48 kms in 6 hours while running upstream. 

II. The boat covers the same distance in 4 hours while running downstream. 

a) I alone sufficient while II alone not sufficient to answer 

b) II alone sufficient while I alone not sufficient to answer 

c) Either I or II alone sufficient to answer 

d) Both I and II are not sufficient to answer 

e) Both I and II are necessary to answer

Answer 1

Correct option: e) Both I and II are necessary to answer

Explanation:

Speed upstream= 48/6 kmph =8 kmph

Speed downstream= 48/4 kmph =12 kmph

Speed of the boat=1/2*(8+12) kmph= 10 kmph

thus I and II together gives the answer. Therefore correct answer is e