A boat covers a certain distance against the stream in 9 hours 36 min and it covers the same distance along the stream in 6 hours. What is the ratio of the speed of the boat in still water to that of the stream?
Let the speed of boat in still water =B and speed of stream =S then Speed of boat in Downstream =B+S, and Time = 6h Speed of boat in Upstream=B-S, Time = 9 h 36min=96/10=48/5h ATQ- 48/5(B-S) =6(B+S) 
B-S=10 … (1) B+S=16 … (2) B=13, S=3 Now ratio of boat speed and stream speed = 13:3
A box contains only three colors of balls- red, green and blue. What is the minimum number of balls that should be picked from the box to ensure that at...
What is the probability that a number selected from 1,2,3.......................68,69,70, is perfect square or a perfect cube?
The probability of selecting a rotten apple randomly from a heap of 150 apples is 0.28. What is the number of rotten apples in the heap?
Tom and Jerry throw alternatively a pair of dice. Tom wins if he throws 8 before Jerry throws 7 and Jerry wins if he throws 7 before Tom throws 8. Find...
A box contains 6 Brown and 8 Blue caps. There is another box which contains 8 Brown and 7 Blue caps. One cap is to drawn from either of the two boxes. ...
36 pens are there in a box where 12 are red pens, ‘p’ are blue pens and remaining are black pens. If a pen is picked, the probability of getting blu...
A bag contains 20 black and 22 white balls. One ball is drawn at random. What is the probability that the ball drawn is white?
...What is the probability that four A’s come consecutively in the word ‘AMALGAMATION’
A bag contains 5 red flowers, 7 yellow flowers and 8 green flowers. 3 flowers are drawn randomly. What is the probability that the flowers drawn contain...
What will be the probability of choosing one red and one green ball from a basket containing 4 red and 5 green balls if two balls are drawn randomly?
