# Created by Mr. Lafferty Maths Dept.

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Created by Mr. Lafferty Maths Dept.
Decimal Numbers MNU 2-03b MNU 2-04a Working with Decimals Decimal Scales Rounding to 1 Decimal Place Addition and Subtraction Multiplying and Dividing by 10, 100, 1000 Multiplying and Dividing by a single Digit 5-Apr-17 Created by Mr. Lafferty Maths Dept.

Created by Mr. Lafferty Maths Dept.
Starter Questions MNU 2-03b MNU 2-04a 5-Apr-17 Created by Mr. Lafferty Maths Dept.

Created by Mr. Lafferty Maths Dept.
Decimal Numbers Writing Decimals MNU 2-03b MNU 2-04a Learning Intention Success Criteria 1. We are learning what a decimal number is. Write down the decimal number represented by a fraction diagram. Understand what a decimal number is. 2. Write down the decimal number represented by a fraction diagram. 5-Apr-17 Created by Mr. Lafferty Maths Dept.

Decimal Numbers www.mathsrevision.com means ten Writing Decimals
MNU 2-03b MNU 2-04a When you take a single unit and divide it into 10 bits, what we then have are decimal fractions of a whole number Imagine, 1 bar of chocolate as our UNIT of measure. 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0 or 0.1 5-Apr-17 Created by Mr. Lafferty Maths Dept.

Created by Mr. Lafferty Maths Dept.
Decimal Numbers Writing Decimals MNU 2-03b MNU 2-04a Example : Write down the decimal number represented by the shaded area. (a) (b) 5-Apr-17 Created by Mr. Lafferty Maths Dept.

Created by Mr. Lafferty Maths Dept.
Decimal Numbers Writing Decimals MNU 2-03b MNU 2-04a Example : Write down the decimal number represented by the diagram. (a) (b) (c) (d) 5-Apr-17 Created by Mr. Lafferty Maths Dept.

Decimal Numbers www.mathsrevision.com Writing Decimals
MNU 2-03b MNU 2-04a We can take one bit of the chocolate bar and split it into 10 1st Decimal place 0.01 0.1 2nd Decimal place 5-Apr-17 Created by Mr. Lafferty Maths Dept.

Created by Mr. Lafferty Maths Dept.
Decimal Numbers Writing Decimals MNU 2-03b MNU 2-04a Example : Write down the decimal number represented by the diagram. (a) (b) (c) (d) 5-Apr-17 Created by Mr. Lafferty Maths Dept.

Created by Mr. Lafferty Maths Dept.
Decimal Numbers Writing Decimals MNU 2-03b MNU 2-04a Now try Exercise 1 Ch2 (page 25) 5-Apr-17 Created by Mr. Lafferty Maths Dept.

Created by Mr. Lafferty Maths Dept.
Starter Questions MNU 2-03b MNU 2-04a 3cm 5-Apr-17 Created by Mr. Lafferty Maths Dept.

Created by Mr. Lafferty Maths Dept.
Decimal Numbers Reading Scales MNU 2-03b MNU 2-04a Learning Intention Success Criteria 1 We are learning the steps to read decimal scales. Understand the steps to work out any decimal scale to 2 decimal places. 2. Solve problems by working out scales. 5-Apr-17 Created by Mr. Lafferty Maths Dept.

Created by Mr. Lafferty Maths Dept.
Decimal Numbers Reading Scales MNU 2-03b MNU 2-04a 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.1 1.2 1.3 1.4 1.5 1.6 1.7 1.8 1.9 0.1 0.0 1.0cm 2.0cm 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 5-Apr-17 Created by Mr. Lafferty Maths Dept.

Created by Mr. Lafferty Maths Dept.
Decimal Numbers Reading Scales MNU 2-03b MNU 2-04a Find the values of the arrows 8 9cm 10cm 8.3 8.8 9.5 9.8 Step 1: Count the number of steps between numbers. In this case it takes 10 steps to get from 8 to 9cm. 10 Step 2: Do the division “ the difference between numbers” by the step number 9-8=1 5-Apr-17 Created by Mr. Lafferty Maths Dept.

Created by Mr. Lafferty Maths Dept.
Decimal Numbers Reading Harder Scales MNU 2-03b MNU 2-04a 3.02 3.04 3.05 3.06 3.07 3.08 3.09 3.11 3.12 3.13 3.14 3.15 3.16 3.17 3.18 3.19 3.01 3.03 3.00cm 3.10cm 3.20cm 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 5-Apr-17 Created by Mr. Lafferty Maths Dept.

Created by Mr. Lafferty Maths Dept.
Decimal Numbers Reading Harder Scales MNU 2-03b MNU 2-04a 12.00cm 12.10cm 12.20cm 12.03 12.08 12.14 12.19 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 5-Apr-17 Created by Mr. Lafferty Maths Dept.

Created by Mr. Lafferty Maths Dept.
Decimal Numbers Reading Scales MNU 2-03b MNU 2-04a Now try Exercise 2 Ch12 (page 28) 5-Apr-17 Created by Mr. Lafferty Maths Dept.

Created by Mr. Lafferty Maths Dept.
Starter Questions MNU 2-03b MNU 2-04a 5-Apr-17 Created by Mr. Lafferty Maths Dept.

Created by Mr. Lafferty Maths Dept.
Decimal Numbers Rounding to 1 decimal place MNU 2-03b MNU 2-04a Learning Intention Success Criteria We are learning how to round to 1 decimal place. 1. Remember steps to round to 1 decimal place. 5-Apr-17 Created by Mr. Lafferty Maths Dept.

Created by Mr. Lafferty Maths Dept.
Decimal Numbers Rounding to 1 decimal place MNU 2-03b MNU 2-04a Find the values of the arrows. 8.2cm 8.3cm 8.4cm 8.24 8.28 8.35 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 5-Apr-17 Created by Mr. Lafferty Maths Dept.

Decimal Numbers www.mathsrevision.com Rounding to 1 decimal place
MNU 2-03b MNU 2-04a The rules for rounding to 1 decimal place are: If the 2nd decimal place is 0,1,2,3,4 - leave 1st decimal place as it is If the 2nd decimal place is 5,6,7,8,9 - add 1 to 1st decimal place Example : Round the numbers to 1 decimal place 9.04 (b) (c) 24.25 (d) (e) (f) 5-Apr-17 Created by Mr. Lafferty Maths Dept.

Created by Mr. Lafferty Maths Dept.
Decimal Numbers Rounding to 1 decimal place MNU 2-03b MNU 2-04a Now try Exercise 3 Ch2 (page 30) 5-Apr-17 Created by Mr. Lafferty Maths Dept.

Created by Mr. Lafferty Maths Dept.
Starter Questions MNU 2-03b MNU 2-04a 5-Apr-17 Created by Mr. Lafferty Maths Dept.

Created by Mr. Lafferty Maths Dept.
Decimal Numbers MNU 2-03b MNU 2-04a Add and Subtract Decimals Learning Intention Success Criteria 1. Understand that you must keep the decimal point lined up when adding and subtracting decimal numbers. 1. We are learning how to add and subtract decimal numbers. 2. Show all working. 5-Apr-17 Created by Mr. Lafferty Maths Dept.

Decimal Numbers www.mathsrevision.com Add and Subtract Decimals
MNU 2-03b MNU 2-04a Add and Subtract Decimals When you add or subtract decimal numbers, it is important to line-up the decimal points. Example 1 : Calculate 5-Apr-17 Created by Mr. Lafferty Maths Dept.

Decimal Numbers www.mathsrevision.com Add and Subtract Decimals
MNU 2-03b MNU 2-04a Add and Subtract Decimals When you add or subtract decimal numbers, it is important to line-up the decimal points. Example 1 : Calculate 4 – 0.84 5-Apr-17 Created by Mr. Lafferty Maths Dept.

Created by Mr. Lafferty Maths Dept.
Decimal Numbers MNU 2-03b MNU 2-04a Add and Subtract Decimals Example 1 : Find the value x cm and y cm x cm y cm 3.91cm 2.1cm y cm 3.25cm 2.2cm x cm 5-Apr-17 Created by Mr. Lafferty Maths Dept.

Created by Mr. Lafferty Maths Dept.
Decimal Numbers MNU 2-03b MNU 2-04a Add and Subtract Decimals Now try Exercise 4 Ch2 (page 32) 5-Apr-17 Created by Mr. Lafferty Maths Dept.

Created by Mr. Lafferty Maths Dept.
Starter Questions MNU 2-03b MNU 2-04a 40o 5-Apr-17 Created by Mr. Lafferty Maths Dept.

Created by Mr. Lafferty Maths Dept.
Decimal Numbers MNU 2-03b MNU 2-04a Multiplying & Dividing by 10, 100, 1000 Learning Intention Success Criteria 1 We are learning how to multiply and divide decimal numbers by 10, 100, 1000. Understand the simple rules to multiply and divide decimal numbers. 2. Be able do calculations. 5-Apr-17 Created by Mr. Lafferty Maths Dept.

Decimal Numbers www.mathsrevision.com Multiplying by 10, 100, 1000
MNU 2-03b MNU 2-04a Multiplying by 10, 100, 1000 To multiply a decimal number by 10, Simply move point 1 place to the right: e.g x 10 = point is moved 1 place to right To multiply a decimal number by 100, Simply move point 2 places to the right: e.g x 100 = point is moved 2 places to right 5-Apr-17 Created by Mr. Lafferty Maths Dept.

Decimal Numbers www.mathsrevision.com Multiplying by 10, 100, 1000
MNU 2-03b MNU 2-04a Multiplying by 10, 100, 1000 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 5-Apr-17 Created by Mr. Lafferty Maths Dept.

Created by Mr. Lafferty Maths Dept.
Decimal Numbers MNU 2-03b MNU 2-04a Multiplying by 10, 100, 1000 Example : Multiply by 10, 100, 1000 10 x = 18.574 100 x = 185.74 1000 x = 1857.4 5-Apr-17 Created by Mr. Lafferty Maths Dept.

Created by Mr. Lafferty Maths Dept.
Decimal Numbers MNU 2-03b MNU 2-04a Multiplying & Dividing y 10, 100, 1000 Now try Ex 5 First Column in each Question ONLY Ch2 (page 35) 5-Apr-17 Created by Mr. Lafferty Maths Dept.

Decimal Numbers www.mathsrevision.com Dividing by 10, 100, 1000
MNU 2-03b MNU 2-04a Dividing by 10, 100, 1000 To divide a decimal number by 10, Simply move point 1 place to the left: e.g. 89 ÷ 10 = 8.9 point is moved 1 place to left To divide a decimal number by 100, Simply move point 2 places to the left: e.g ÷ 100 = point is moved 2 places to left 5-Apr-17 Created by Mr. Lafferty Maths Dept.

Decimal Numbers www.mathsrevision.com Dividing by 10, 100, 1000
MNU 2-03b MNU 2-04a Dividing by 10, 100, 1000 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 5-Apr-17 Created by Mr. Lafferty Maths Dept.

Created by Mr. Lafferty Maths Dept.
Decimal Numbers MNU 2-03b MNU 2-04a Dividing by 10, 100, 1000 Example : Divide by 10, 100, 1000 ÷ 10 = 4502.4 ÷ 100 = 450.24 ÷ 1000 = 45.024 5-Apr-17 Created by Mr. Lafferty Maths Dept.

Created by Mr. Lafferty Maths Dept.
Decimal Numbers MNU 2-03b MNU 2-04a Multiplying & Dividing y 10, 100, 1000 Now try Ex 6 First Column in each Question ONLY Ch2 (page 35) 5-Apr-17 Created by Mr. Lafferty Maths Dept.

Created by Mr. Lafferty Maths Dept.
Starter Questions MNU 2-03b MNU 2-04a 57o 5-Apr-17 Created by Mr. Lafferty Maths Dept.

Created by Mr. Lafferty Maths Dept.
Decimal Numbers MNU 2-03b MNU 2-04a Multiplication & Division by a Single Digit Learning Intention Success Criteria 1. Understand how to multiply and divide a decimal number by a single Digit. 1. We are learning how to multiply and divide a decimal number by a single Digit. 2. Show appropriate working. 5-Apr-17 Created by Mr. Lafferty Maths Dept.

Decimal Numbers www.mathsrevision.com
MNU 2-03b MNU 2-04a Multiplication & Division by a Single Digit When multiplying by a single digit the decimal point always stays in line. Example : Calculate x 7 5-Apr-17 Created by Mr. Lafferty Maths Dept.

Decimal Numbers www.mathsrevision.com
MNU 2-03b MNU 2-04a Multiplication & Division by a Single Digit When dividing by a single digit the decimal point always stays in line. Example : Calculate ÷ 6 5-Apr-17 Created by Mr. Lafferty Maths Dept.

Created by Mr. Lafferty Maths Dept.
Decimal Numbers MNU 2-03b MNU 2-04a Multiplication & Division by a Single Digit Example : Copy and complete. 3.5 x 6 18.43 x 4 76.97 x 6 ÷ 6 6.52 ÷ 2 95.05 ÷ 5 5-Apr-17 Created by Mr. Lafferty Maths Dept.

Created by Mr. Lafferty Maths Dept.
Decimal Numbers MNU 2-03b MNU 2-04a Multiplication & Division by a Single Digit Now try Ex 7 & 8 Ch2 (page 37) 5-Apr-17 Created by Mr. Lafferty Maths Dept.