Presentation is loading. Please wait.

Presentation is loading. Please wait.

25-Aug-14Created by Mr. Lafferty Maths Dept. Working with Decimals Decimal Scales Decimal Numbers www.mathsrevision.com Multiplying and Dividing by 10,

Similar presentations


Presentation on theme: "25-Aug-14Created by Mr. Lafferty Maths Dept. Working with Decimals Decimal Scales Decimal Numbers www.mathsrevision.com Multiplying and Dividing by 10,"— Presentation transcript:

1 25-Aug-14Created by Mr. Lafferty Maths Dept. Working with Decimals Decimal Scales Decimal Numbers Multiplying and Dividing by 10, 100, 1000 Multiplying and Dividing by a single Digit Rounding to 1 Decimal Place Addition and Subtraction MNU 2-03b MNU 2-04a

2 25-Aug-14Created by Mr. Lafferty Maths Dept. Starter Questions Starter Questions MNU 2-03b MNU 2-04a

3 25-Aug-14Created by Mr. Lafferty Maths Dept. Learning Intention Success Criteria 1.Understand what a decimal number is. 1. We are learning what a decimal number is. Write down the decimal number represented by a fraction diagram. Decimal Numbers 2.Write down the decimal number represented by a fraction diagram. Writing Decimals MNU 2-03b MNU 2-04a

4 25-Aug-14Created by Mr. Lafferty Maths Dept. Decimal Numbers When you take a single unit and divide it into 10 bits, what we then have are decimal fractions of a whole number Writing Decimals Imagine, 1 bar of chocolate as our UNIT of measure. or means ten MNU 2-03b MNU 2-04a

5 25-Aug-14Created by Mr. Lafferty Maths Dept. Decimal Numbers Writing Decimals Example : Write down the decimal number represented by the shaded area. (a) (b) MNU 2-03b MNU 2-04a

6 25-Aug-14Created by Mr. Lafferty Maths Dept. Decimal Numbers Writing Decimals Example : Write down the decimal number represented by the diagram. (a)(b) (c)(d) MNU 2-03b MNU 2-04a

7 25-Aug-14Created by Mr. Lafferty Maths Dept. Decimal Numbers We can take one bit of the chocolate bar and split it into 10 Writing Decimals st Decimal place 2 nd Decimal place MNU 2-03b MNU 2-04a

8 25-Aug-14Created by Mr. Lafferty Maths Dept. Decimal Numbers Writing Decimals Example : Write down the decimal number represented by the diagram. (a)(b) (c)(d) MNU 2-03b MNU 2-04a

9 25-Aug-14Created by Mr. Lafferty Maths Dept. Now try Exercise 1 Ch2 (page 25) Decimal Numbers Writing Decimals MNU 2-03b MNU 2-04a

10 25-Aug-14Created by Mr. Lafferty Maths Dept. Starter Questions Starter Questions 3cm MNU 2-03b MNU 2-04a

11 25-Aug-14Created by Mr. Lafferty Maths Dept. Learning Intention Success Criteria 1.Understand the steps to work out any decimal scale to 2 decimal places. 1 We are learning the steps to read decimal scales. Decimal Numbers 2.Solve problems by working out scales. Reading Scales MNU 2-03b MNU 2-04a

12 25-Aug-14Created by Mr. Lafferty Maths Dept. You must work out what number goes next to each mark on the scale. Step 1:Count the number of steps between numbers. In this case it takes 10 steps to get from 0.0 to 1.0cm. Step 2:Do the division “ the difference between numbers” by the step number cm 2.0cm Decimal Numbers Reading Scales MNU 2-03b MNU 2-04a

13 25-Aug-14Created by Mr. Lafferty Maths Dept. Find the values of the arrows cm 10cm Step 1:Count the number of steps between numbers. In this case it takes 10 steps to get from 8 to 9cm. Step 2:Do the division “ the difference between numbers” by the step number 9-8=1 10 Decimal Numbers Reading Scales MNU 2-03b MNU 2-04a

14 25-Aug-14Created by Mr. Lafferty Maths Dept. You must work out what number goes next to each mark on the scale. Step 1:Count the number of steps between numbers. In this case it takes 10 steps to get from 3.00cm to 3.10cm. Step 2:Do the division “ the difference between numbers” by the step number 3.00cm 3.10cm 3.20cm Decimal Numbers Reading Harder Scales MNU 2-03b MNU 2-04a

15 25-Aug-14Created by Mr. Lafferty Maths Dept. Step 1:Count the number of steps between numbers. In this case it takes 10 steps to get from 12.00cm to 12.10cm. Step 2:Do the division “ the difference between numbers” by the step number cm 12.10cm 12.20cm Decimal Numbers Reading Harder Scales MNU 2-03b MNU 2-04a

16 25-Aug-14Created by Mr. Lafferty Maths Dept. Now try Exercise 2 Ch12 (page 28) Decimal Numbers Reading Scales MNU 2-03b MNU 2-04a

17 25-Aug-14Created by Mr. Lafferty Maths Dept. Starter Questions Starter Questions MNU 2-03b MNU 2-04a

18 25-Aug-14Created by Mr. Lafferty Maths Dept. Learning Intention Success Criteria 1.We are learning how to round to 1 decimal place. Decimal Numbers 1.Remember steps to round to 1 decimal place. Rounding to 1 decimal place MNU 2-03b MNU 2-04a

19 25-Aug-14Created by Mr. Lafferty Maths Dept. 8.2cm 8.3cm 8.4cm Decimal Numbers Rounding to 1 decimal place Find the values of the arrows. Is 8.24 nearer to 8.2 or 8.3 ?8.2 Is 8.28 nearer to 8.2 or 8.3 ?8.3 Is 8.35 nearer to 8.2 or 8.3 ?Neither MNU 2-03b MNU 2-04a

20 25-Aug-14Created by Mr. Lafferty Maths Dept. Decimal Numbers Rounding to 1 decimal place If the 2 nd decimal place is 0,1,2,3,4 - leave 1 st decimal place as it is Example :Round the numbers to 1 decimal place (a) 9.04(b)18.08(c)24.25 (d)12.73(e)102.09(f) If the 2 nd decimal place is 5,6,7,8,9 - add 1 to 1 st decimal place The rules for rounding to 1 decimal place are: MNU 2-03b MNU 2-04a

21 25-Aug-14Created by Mr. Lafferty Maths Dept. Now try Exercise 3 Ch2 (page 30) Decimal Numbers Rounding to 1 decimal place MNU 2-03b MNU 2-04a

22 25-Aug-14Created by Mr. Lafferty Maths Dept. Starter Questions Starter Questions MNU 2-03b MNU 2-04a

23 25-Aug-14Created by Mr. Lafferty Maths Dept. Learning Intention Success Criteria 1. We are learning how to add and subtract decimal numbers. 1. Understand that you must keep the decimal point lined up when adding and subtracting decimal numbers. Decimal Numbers 2. Show all working. Add and Subtract Decimals MNU 2-03b MNU 2-04a

24 25-Aug-14Created by Mr. Lafferty Maths Dept. Decimal Numbers Example 1 :Calculate When you add or subtract decimal numbers, it is important to line-up the decimal points. Add and Subtract Decimals MNU 2-03b MNU 2-04a

25 25-Aug-14Created by Mr. Lafferty Maths Dept. Decimal Numbers Example 1 :Calculate 4 – 0.84 When you add or subtract decimal numbers, it is important to line-up the decimal points. Add and Subtract Decimals MNU 2-03b MNU 2-04a

26 25-Aug-14Created by Mr. Lafferty Maths Dept. Decimal Numbers Example 1 : Find the value x cm and y cm Add and Subtract Decimals 2.1cm 3.91cm x cm x cmy cm y cm 3.25cm 2.2cm MNU 2-03b MNU 2-04a

27 25-Aug-14Created by Mr. Lafferty Maths Dept. Now try Exercise 4 Ch2 (page 32) Decimal Numbers Add and Subtract Decimals MNU 2-03b MNU 2-04a

28 25-Aug-14Created by Mr. Lafferty Maths Dept. Starter Questions Starter Questions 40 o MNU 2-03b MNU 2-04a

29 25-Aug-14Created by Mr. Lafferty Maths Dept. Learning Intention Success Criteria 1.Understand the simple rules to multiply and divide decimal numbers. 1 We are learning how to multiply and divide decimal numbers by 10, 100, Be able do calculations. Decimal Numbers Multiplying & Dividing by 10, 100, 1000 MNU 2-03b MNU 2-04a

30 25-Aug-14Created by Mr. Lafferty Maths Dept. Decimal Numbers To multiply a decimal number by 10, Simply move point 1 place to the right: e.g.2.55 x 10 = 25.5point is moved 1 place to right Multiplying by 10, 100, 1000 To multiply a decimal number by 100, Simply move point 2 places to the right: e.g.1.02 x 100 = point is moved 2 places to right MNU 2-03b MNU 2-04a

31 25-Aug-14Created by Mr. Lafferty Maths Dept. Decimal Numbers To multiply a decimal number by 1000, Simply move point 3 places to the right: e.g x 1000 = point is moved 1 place to right Multiplying by 10, 100, 1000 MNU 2-03b MNU 2-04a

32 25-Aug-14Created by Mr. Lafferty Maths Dept. Decimal Numbers Example : Multiply by 10, 100, x = 100 x = 1000 x = Multiplying by 10, 100, 1000 MNU 2-03b MNU 2-04a

33 25-Aug-14Created by Mr. Lafferty Maths Dept. Now try Ex 5 First Column in each Question ONLY Ch2 (page 35) Decimal Numbers Multiplying & Dividing y 10, 100, 1000 MNU 2-03b MNU 2-04a

34 25-Aug-14Created by Mr. Lafferty Maths Dept. Decimal Numbers To divide a decimal number by 10, Simply move point 1 place to the left: e.g.89 ÷ 10 = 8.9point is moved 1 place to left Dividing by 10, 100, 1000 To divide a decimal number by 100, Simply move point 2 places to the left: e.g.199 ÷ 100 = 1.99point is moved 2 places to left MNU 2-03b MNU 2-04a

35 25-Aug-14Created by Mr. Lafferty Maths Dept. Decimal Numbers To divide a decimal number by 1000, Simply move point 3 places to the left: e.g ÷ 1000 = point is moved 3 places to the left Dividing by 10, 100, 1000 MNU 2-03b MNU 2-04a

36 25-Aug-14Created by Mr. Lafferty Maths Dept. Decimal Numbers Example : Divide by 10, 100, ÷ 10 = ÷ 100 = ÷ 1000 = Dividing by 10, 100, 1000 MNU 2-03b MNU 2-04a

37 25-Aug-14Created by Mr. Lafferty Maths Dept. Now try Ex 6 First Column in each Question ONLY Ch2 (page 35) Decimal Numbers Multiplying & Dividing y 10, 100, 1000 MNU 2-03b MNU 2-04a

38 25-Aug-14Created by Mr. Lafferty Maths Dept. Starter Questions Starter Questions 57 o MNU 2-03b MNU 2-04a

39 25-Aug-14Created by Mr. Lafferty Maths Dept. Learning Intention Success Criteria 1. We are learning how to multiply and divide a decimal number by a single Digit. 1. Understand how to multiply and divide a decimal number by a single Digit. Decimal Numbers 2. Show appropriate working. Multiplication & Division by a Single Digit MNU 2-03b MNU 2-04a

40 25-Aug-14Created by Mr. Lafferty Maths Dept. Decimal Numbers When multiplying by a single digit the decimal point always stays in line. Example :Calculate x 7 Multiplication & Division by a Single Digit MNU 2-03b MNU 2-04a

41 25-Aug-14Created by Mr. Lafferty Maths Dept. Decimal Numbers When dividing by a single digit the decimal point always stays in line. Example :Calculate ÷ 6 Multiplication & Division by a Single Digit MNU 2-03b MNU 2-04a

42 25-Aug-14Created by Mr. Lafferty Maths Dept. Example : Copy and complete. 3.5 x x x ÷ ÷ ÷ 6 Decimal Numbers Multiplication & Division by a Single Digit MNU 2-03b MNU 2-04a

43 25-Aug-14Created by Mr. Lafferty Maths Dept. Now try Ex 7 & 8 Ch2 (page 37) Decimal Numbers Multiplication & Division by a Single Digit MNU 2-03b MNU 2-04a


Download ppt "25-Aug-14Created by Mr. Lafferty Maths Dept. Working with Decimals Decimal Scales Decimal Numbers www.mathsrevision.com Multiplying and Dividing by 10,"

Similar presentations


Ads by Google