Cirrce Problems from Poland
- 1. 1. A circular tablecloth has diameter 1 m. The designer wants to put a fringe around the edge of the cloth. How much fringe should he buy, if fringe is sold by the tenth of a metre? Explain. 3. A car wheel has a diameter of 50cm. How far will the car travel if the wheel turns 5 times? If the same car wheel turns 500 times, find the distance travelled correct to the nearest metre. 4. A bicycle wheel has a diameter of 65cms. How many turns will it make while travelling a distance of 2km? 5. Mary has a circular dining table with a radius of 0.65m. Work out the area of the top of the table. Give your answer to 3 significant figures. The perimeter of the circular tablecloth is 5m. Work out the diameter of the tablecloth. 6. Bob has a circular lawn with a radius of 2.2 m. He has a 1 kg box of lawn feed. The label says ‘Use 75 g diluted in 4 litres of water per square metre of lawn’. Does Bob have enough lawn feed for his lawn? 7. A sprinkler can spray water 5 metres out in all directions. How much area can the sprinkler water? 8. The surface of a table consists of a square of side 1 m e and two semicircles attached on either opposite end. Calculate the area of the table. 9. A circular flowerbed has a radius of 1.6m. Calculate the area of the flowerbed. 10. The following is an athletics track. The two straights are 150m, and the curved sections both have a radius of 25m. The inside of the track, the green area, is to be covered in grass for use in other athletics events. What is the total area of grass needed?
- 2. 11. The train on a children’s roundabout goes round in a circle of diameter 6m. Calculate the circumference of the circle James rides on the train and travels 165m. How many complete turns does he go round? The floor of the roundabout has a radius 3.5m. Calculate the area of the floor. 12. An umbrella has 10 ribs which are equally spaced. Assuming umbrella to be a flat circle of radius 40 cm, find the area between the two consecutive ribs of the umbrella. 13. The beam from a lighthouse reaches a distance of 8 kilometres and spreads to an angle of 35°. Calculate the area covered by the beam from the lighthouse. 14. The radar beam sent out by an aeroplane reaches a distance of 120 kilometres and covers an angle of 150°.Calculate the area covered by the beam. 15. A windscreen wiper is 45 centimetres long. In one sweep it turns through an angle of 115°. Calculate the distance it covers in one sweep. 16. Some oil is spilt. The spilt oil is in the shape of a circle. The circle has a diameter of 12 centimetres. Work out the circumference, in centimeters, of the spilt oil. Give your answer correct to 1 decimal place. 17. The diagram shows a window. The arc AB is a semicircle. BC = AD = 75cm, DC = 80cm. Calculate the area of the window.