Question
A policeman noticed a thief at a distance of 500 metres.
The policeman started running and the thief also started running at the same time. The thief is running at a speed of 15 km/h. It took 15 minutes for the policeman to catch the thief. Find the speed of the policeman (in km/h).ÂSolution
Let the speed of the policeman be x km/h. The thief runs at 15 km/h and was 500 meters (0.5 km) ahead. Time taken to catch the thief is 15 minutes = 0.25 hours. Relative speed = x − 15 km/h Distance = 0.5 km Time = 0.25 hours Using the formula: Distance = Speed ×Time 0.5 =(x − 15) × 0.25 0.5/0.25 = x − 15 2 = x − 15 x = 17
If the length and breadth of a rectangle are each increased by 4 m, its area increases by 224 m². The ratio of the perimeter of the square to that of t...
If the word PHOTOGRAPH is spelt with ‘F’ in place of ‘PH', then what would be the percentage reduction in the number of letters?
Curved surface area of cylinder is 215.6 cm2. If ratio of radius to height of the cylinder is 10:4 respectively, then find the base area of t...
- The volume of a sphere is 3888 cm³. Calculate the surface area (in cm²) of the sphere. [Use π = 3]
The difference between the length and breadth of a rectangle is 27 m. If its perimeter is 194 m, then its area is
Cylinder radius = 7 cm, height = 12 cm. It is melted into cones of radius 3.5 cm, height 8 cm. Find number of cones.
The ratio of the largest and the smallest angle of a triangle is 3:2. The smallest angle is 80% of the sum of these two angles. What is the sum of the r...
The area of a square field is 800 sq m. How long in seconds will a lady take to cross the field diagonally at the rate of 4.8 km/hr?
Consider a circle and a square whose circumference ratio is 11:8. If the sum of the circle's radius and the length of one side of the square equals 30 c...
Relevant for Exams:
