Question
Naveen walking at a speed of 15 km/h reaches his office
20 minutes late. Next time he increases his speed by 5 km/h, but he finds he is still late by 5 minutes. What is the distance of his office from his house?Solution
Let the distance be D. D/15 = T + 20/60 ……. (i) D/20 = T + 5/60 ……. (i) Form (i) and (ii) we get, D x 1/60 = 15/60 D = 15 km. Alternate method: Distance = Time gap× product of speeds/ gap of speed = 15 min×15×20/(20-15) = 15/60 hrs ×15×20/5 = 15 Km
- 25 defective watches got mixed with 175 non-defective watches. A buyer purchases one watch. What is the probability that the watch is defective?
14 defective fans were accidentally mixed with 126 non-defective fans. One fan is randomly selected. Find the probability that it is a defective fan.
In a lottery, there are 6 prizes and 30 blanks. A lottery is drawn at random. What is the probability of getting a prize?
...A bag contains 7 white, 13 orange and 10 brown balls. Two balls are randomly drawn from the bag, what is the probability that a white and a brown ball a...
There are 14 boys and 6 girls giving interview for a job. If three of them are selected, then what is the probability that one of the three is a girl an...
John bought a watch for Rs. 3,400 and sold it at a profit percentage equal to the profit percentage earned on selling 10 bicycles for the cost price of ...
A bag contains 6 Green and 8 Red balls. One ball is drawn at random. What is the probability that the ball drawn is Red?
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...
Out of three girls and five boys, five children are to be randomly selected for a dance programme. What is the probability that all the selected childre...
Rohan divided a two-digit number by '7', what is the probability that the remainder obtained is a prime number?
