significant figures ppt.ppt

significant figures ppt.ppt

• 1.
  FA Cup Final Roundingto Significant Figures
• 2.
  • To recalland use the rules of rounding up and down. • To be able to round any integer to a significant figure. • To understand and explain the difference between rounding to decimal places and rounding to significant figures. • To be able to round to significant figures. Learning Objective Success Criteria
• 3.
  Starter: What’s YourCapacity?
• 4.
  Rounding Rules What areour rounding rules? 4 or less, let it rest. 5 or more, let it soar.
• 5.
  Significant Figures Sometimes wedo not always need to give detailed answers to problems – we can estimate an answer. To do this, we can use significant figures. In maths, significant means ‘to have value’. Examples In the number 2795, the 2 is the most significant digit, because it tells us that the number is 2 thousand and something. However, in the number 0.052, the 5 is the most significant digit.
• 6.
  Significant Figures When weround to significant figures, we start counting as soon as we reach a number that is not zero. Round 37 to 1 significant figure. Round 37 to 1 significant figure = 40 1 significant figure To work out if the 30 will remain the same or round up to 40, we need to look at the column to its right (the units column). In this case, the number next to it is worth 7 units, so we round our 30 up to 40.
• 7.
  Significant Figures Round 153to 2 significant figures. Remember: we need to look to the right of the ‘50’ to find out if this will remain 50 or be rounded up to 60. On this occasion, because the number to its right is a 3, it means that 153 rounded to 2 significant figures is 150. 1 significant figure 2 significant figures
• 8.
  Significant Figures What would153 rounded to 1 significant figure be? We need to look to the right of our ‘100’ to find out if this will remain the same or be rounded up to 200. On this occasion, the number to its right (in the tens) is a 5, therefore 100 will need to be rounded to 200. 153 rounded to 1 significant figure is 200. 1 significant figure
• 11.
  Quick-Fire Significant Figures Answerthe following questions by applying your understanding of rounding significant figures. 1) Round 45 to 1 significant figure. 2) Round 192 to 2 significant figures. 3) Sally says that 136.248 rounded to 2 significant figures is 136.25. a) Explain the mistake that Sally has made. b) What is the correct answer? 50 190 She has rounded to 2 decimal places instead of 2 significant figures. 140
• 12.
  Plenary: What’s theDifference? Explain the difference between rounding to significant figures and rounding to decimal places. Extension: Can you link your explanation to the FA Cup Final?
• 13.
  Plenary: Significant FiguresExtension Round 0.00287 to 2 significant figures.