Significant Figures

Significant Figures Numbers can be rounded to a given number of significant figures 275300 This is the first significant figure This is the first significant figure 0.0003672 The first significant figure is the first non-zero number

Significant Figures Numbers can be rounded to a given number of significant figures 275300 This is the second significant figure This is the second significant figure 0.0003672

This is the first significant figure Round up or stay the same? Significant Figures Round 275300 to 1 significant figure This is the first significant figure 275,300 Round up or stay the same? Round up! 3 00,000

Mini-Whiteboards Significant Figures

This is the first significant figure What is the first significant figure? 0.00745 This is the first significant figure

This is the third significant figure What is the third significant figure? 0.00745 This is the third significant figure

This is the fourth significant figure What is the fourth significant figure? 302700 This is the fourth significant figure

This is the third significant figure What is the third significant figure? 0.002074 This is the third significant figure

This is the first significant figure What is the first significant figure? 307482 This is the first significant figure

This is the second significant figure Round up or stay the same? Significant Figures Round 275300 to 2 significant figures This is the second significant figure 275,300 Round up or stay the same? Round up! 28 0,000

This is the first significant figure Round up or stay the same? Significant Figures Round 0.00325 to 1 significant figure This is the first significant figure 0.00325 Round up or stay the same? Stay the same 0.003

This is the first significant figure Round up or stay the same? Significant Figures Round 36.7 to 1 significant figure This is the first significant figure 36.7 Round up or stay the same? Round up! 40 .0

This is the second significant figure Round up or stay the same? Significant Figures Round 36.7 to 2 significant figures This is the second significant figure 36.7 Round up or stay the same? Round up! 37 .0

Significant Figures Number To 3 s.f. To 2 s.f. To 1 s.f. 4213   6435 23.65 43.89 0.0465 0.009231 0.9649 0.4054 0.07008 0.4109 0.005007

Significant Figures Number To 3 s.f. To 2 s.f. To 1 s.f. 4213 4210 4200 4000 6435 6440 6400 6000 23.65 23.7 24 20 43.89 43.9 44 40 0.0465 0.047 0.05 0.009231 0.00923 0.0092 0.009 0.9649 0.965 0.96 1 0.4054 0.405 0.41 0.4 0.07008 0.701 0.70 0.07 0.4109 0.411 0.005007 0.00501 0.0050 0.005

0.0235 Significant Figures – Can you spot the error? This is the first significant figure 0.0235

Significant Figures – Can you spot the error? 0.769

Estimating using Significant Figures We can use significant figures to quickly estimate answers Round to 1 sf Round to 1 sf 45 × 34 50 × 30 =1500

Estimating using Significant Figures Round to 1 sf 𝟑𝟔×𝟐𝟐 𝟐.𝟑𝟕 Round to 1 sf Round to 1 sf 40 × 20 = 𝟖𝟎𝟎 𝟐 =𝟒𝟎𝟎 2

Estimating using Significant Figures Screws cost £2.90 per packet. How much would 21 packets cost? Round to 1 sf Round to 1 sf £3.00 × 20 = £60