Question
A is cycling at an average speed of 11 km/hr such that
he can reach a certain point at 12 noon. If he cycles at 22 km/hr, then he will reach the destination at 10 a.m. At what speed he should cycle to reach the destination at 11 a.m.Solution
Let the distance to be travelled be ‘x’ km Time taken when speed is 11 km/hr = (x/11) hours Time taken when speed is 22 km/hr = (x/22) hours According to the question, (x/11) – (x/22) = 2 Or, 2x – x = 2 × 22 Or, x = 44 km Time taken to travel 44 km with speed of 11 km/hr = 44/11 = 4 hours Therefore, he started at 12 – 4 = 8 a.m. Therefore, required speed to reach the destination at 11 a.m. or 4 hours = 44/3 = 14.66 km/hr
A bag has 4 red, 3 blue, and 3 green balls. Two are drawn without replacement. Find probability that both are of different colors.
- The letters of the word MISCHIEF are arranged among themselves. What is the probability that word ICE will be contained?
One bag contains 5 yellow hats and 4pink hats. Another bag contains 3 yellow hats and 7pink hats. If one hat is drawn from each bag, what is the probabi...
17 rotten bananas are accidentally mixed with 120 good ones. It is not possible to just look at a banana and tell whether or not it is rotten. One banan...
One five letter word is to be formed taking all letters – U, Z, M, O and Q. What is the probability that this is word formed will contain all vowe...
A bag has 7 pink, 4 black and 3 yellow balls while another bag has 5 pink, 6 yellow and 3 blue balls. A bag is selected at random and a ball drawn out ...
The probability of selecting a rotten egg randomly from a basket of 250 eggs is 0.2. What is the number of rotten eggs in the basket?
16 rotten bananas are accidentally mixed with 155 good ones. It is not possible to just look at a banana and tell whether or not it is rotten. One banan...
- A container holds 7 orange balls, 5 violet balls and 8 grey balls. Two balls are drawn at random. What is the probability that at least one of them is viol...
A box has ‘x’ black marbles, ‘x + 5’ blue marbles and ‘x – 1’ yellow marbles. If the probability of selecting a yellow marble is 1/28 less...
