1 Accuracy & Precision Press Ctrl-A ©2009 – Not to be sold/Free to use Stage 4 - Year 7

2 Accuracy & Precision All measurements are accurate to within ± 0.5 of the smallest unit on the measuring device. = 4 cm Error = ±0.5 cm Actual Length lies between =4.5cm 4 – 0.5 =3.5cm End of Slide

3 What decree of accuracy would be needed when measuring a … ? a) Lighthouse metres b) Soccer ball centimetres Accuracy & Precision End of Slide

4 Between what two limits does 75m lie if measured with a trundle wheel to the nearest metre? Lower = = 74.5 m Upper = = 75.5 m Error = ±0.5 m Accuracy & Precision End of Slide

5 Between what two limits does 360cm lie if measured with a decimetre tape to the nearest 10cm? Lower = = 355 cm Upper = = 365 cm Decimetre tape Error = ± 5 cm Accuracy & Precision End of Slide

6 Between what two limits does 500 km lie if measured with a odometer to the nearest 5km? Lower = = km Upper = = km Odometer Error = ± 2.5 km Accuracy & Precision End of Slide

7 A building’s height was measured as 93 metres to the nearest metre. limits Between what limits does it lie? Range Range = 93 ± 0.5 metres Between 92.5m and 93.5 m. Accuracy & Precision End of Slide

8 80cm 10cm A ball was measured as 80cm to the nearest 10cm. limits Between what limits does it lie? Range Range = 80 ± 5cm Between 75cm and 85 cm. Accuracy & Precision End of Slide

9 Port Macquarie Sydney 500km 100km The distance from Port Macquarie to Sydney is given as 500km to the nearest 100km. limits Between what limits does it lie? Range Range = 500 ± 50km Between 550km and 650km. Accuracy & Precision End of Show