**21. Walking at 3/4th of his regular speed, Sanjay is 16 minutes late in reaching the office. Find the usual time that he takes to reach the office. **

**22. A train moves at a constant speed of 120 km/hr for one km and at 40 km/hr for the next km. Find the average speed of the train. **

**23. A can finish a piece of work in 10, while B can finish it in 20 days. They start working together and after 5 days, A leaves the job. Find the number of days in which B will finish the remaining work. **

**24. At what exact time between 5 and 6 will the two hands of a clock be at an angle of 180 degrees **

**25. An integer is chosen at random from 1 to 100. Find the probability that it is a multiple of 5 or 8. **

**26. A ship went on a voyage. After it had traveled 180 miles a plane started with 10 times the speed of the ship. Find the distance when they meet from starting point. **

**27. Three friends divided some bullets equally. After all of them shot 4 bullets the total number of bullets remaining is equal to the bullets each had after division. Find the original number divided. **

**28. A hotel has 10 floors. Which floor is above the floor below the floor, below the floor above the floor, below the floor above the fifth? **

**29. Two trains starting at same time, one from Bangalore to Mysore and other in opposite direction arrive at their destination 1 hr and 4 hours respectively after passing each other. How much faster is one train from other? **

**30. Father's age is three years more than three times the son's age. After three years, father's age will be ten years more than twice the son's age. What is the father's present age? **