Created by Mr. Lafferty Maths Dept. Decimal Numbers Working with Decimals Decimal Scales Rounding to nearest whole number www.mathsrevision.com Rounding to 1 Decimal Place Addition and Subtraction 8-Jan-18 Created by Mr. Lafferty Maths Dept.

Created by Mr. Lafferty Maths Dept. Starter Questions www.mathsrevision.com 8-Jan-18 Created by Mr. Lafferty Maths Dept.

Created by Mr. Lafferty Maths Dept. Decimal Numbers Writing Decimals 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. www.mathsrevision.com 8-Jan-18 Created by Mr. Lafferty Maths Dept.

Decimal Numbers www.mathsrevision.com means ten Writing Decimals 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. www.mathsrevision.com 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0 or 0.1 8-Jan-18 Created by Mr. Lafferty Maths Dept.

Created by Mr. Lafferty Maths Dept. Decimal Numbers Writing Decimals Example : Write down the decimal number represented by the shaded area. (a) www.mathsrevision.com (b) 8-Jan-18 Created by Mr. Lafferty Maths Dept.

Created by Mr. Lafferty Maths Dept. Decimal Numbers Writing Decimals Example : Write down the decimal number represented by the diagram. (a) (b) www.mathsrevision.com (c) (d) 8-Jan-18 Created by Mr. Lafferty Maths Dept.

Decimal Numbers www.mathsrevision.com Writing Decimals We can take one bit of the chocolate bar and split it into 10 1st Decimal place 0.01 0.1 www.mathsrevision.com 2nd Decimal place 8-Jan-18 Created by Mr. Lafferty Maths Dept.

Created by Mr. Lafferty Maths Dept. Decimal Numbers Writing Decimals Example : Write down the decimal number represented by the diagram. (a) (b) www.mathsrevision.com (c) (d) 8-Jan-18 Created by Mr. Lafferty Maths Dept.

Created by Mr. Lafferty Maths Dept. Decimal Numbers Writing Decimals Now try TJ2a Ex 1 Ch5 (page 37) www.mathsrevision.com 8-Jan-18 Created by Mr. Lafferty Maths Dept.

Created by Mr. Lafferty Maths Dept. Starter Questions 3cm www.mathsrevision.com 8-Jan-18 Created by Mr. Lafferty Maths Dept.

Created by Mr. Lafferty Maths Dept. Decimal Numbers Reading Scales 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. www.mathsrevision.com 8-Jan-18 Created by Mr. Lafferty Maths Dept.

Created by Mr. Lafferty Maths Dept. Decimal Numbers Reading Scales 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 0.0cm 1.0cm 2.0cm You must work out what number goes next to each mark on the scale. www.mathsrevision.com 8-Jan-18 Created by Mr. Lafferty Maths Dept.

Created by Mr. Lafferty Maths Dept. Decimal Numbers Reading Scales Find the values of the arrows 8cm 9cm 10cm 8.3 8.8 9.5 9.8 www.mathsrevision.com 8-Jan-18 Created by Mr. Lafferty Maths Dept.

Created by Mr. Lafferty Maths Dept. Decimal Numbers Reading Harder Scales 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. www.mathsrevision.com 8-Jan-18 Created by Mr. Lafferty Maths Dept.

Created by Mr. Lafferty Maths Dept. Decimal Numbers Reading Harder Scales 12.00cm 12.10cm 12.20cm 12.03 12.08 12.14 12.19 www.mathsrevision.com 8-Jan-18 Created by Mr. Lafferty Maths Dept.

Created by Mr. Lafferty Maths Dept. Decimal Numbers Reading Scales Now try TJ2a Ex 2 Ch5 (page 41) www.mathsrevision.com 8-Jan-18 Created by Mr. Lafferty Maths Dept.

The answer to the question is Starter Questions The answer to the question is 60 www.mathsrevision.com Write down as many questions as you can 8-Jan-18 Created by Mr. Lafferty Maths Dept.

Created by Mr. Lafferty Maths Dept. Rounding Learning Intention Success Criteria 1. Use previous knowledge to help round to any number to the nearest whole number. 1. We are learning to round to the nearest whole number. www.mathsrevision.com 8-Jan-18 Created by Mr. Lafferty Maths Dept.

Rounding 2.4 2 2.7 3 www.mathsrevision.com 2.5 3 All to do with the number 5 Rounding Rounding to the nearest whole number we look at the first decimal place : 2.4 since 4 is less than 5 nearest whole number is 2 2.7 since 7 is more than 5 nearest whole number is 3 www.mathsrevision.com ? 2.5 since 5 is not less than 5 nearest whole number is 3 8-Jan-18 Created by Mr. Lafferty Maths Dept.

Rounding 432.67 433 www.mathsrevision.com 596.55 597 13.05 13 All to do with the number 5 Rounding Round the following to the nearest whole number. 432.67 433 www.mathsrevision.com 596.55 597 13.05 13 8-Jan-18 Created by Mr. Lafferty Maths Dept.

Created by Mr. Lafferty Maths Dept. Decimal Numbers Reading Scales Now try TJ2a Ex 3 Ch5 (page 44) www.mathsrevision.com 8-Jan-18 Created by Mr. Lafferty Maths Dept.

Created by Mr. Lafferty Maths Dept. Starter Questions www.mathsrevision.com 8-Jan-18 Created by Mr. Lafferty Maths Dept.

Created by Mr. Lafferty Maths Dept. Decimal Numbers Rounding to 1 decimal place Learning Intention Success Criteria We are learning how to round to 1 decimal place. 1. Remember steps to round to 1 decimal place. www.mathsrevision.com 8-Jan-18 Created by Mr. Lafferty Maths Dept.

Created by Mr. Lafferty Maths Dept. Decimal Numbers Rounding to 1 decimal place Find the values of the arrows. 8.2cm 8.3cm 8.4cm 8.24 8.28 8.35 www.mathsrevision.com 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 8-Jan-18 Created by Mr. Lafferty Maths Dept.

Decimal Numbers www.mathsrevision.com Rounding to 1 decimal place 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) 18.08 (c) 24.25 (d) 12.73 (e) 102.09 (f) 2636.55 www.mathsrevision.com 8-Jan-18 Created by Mr. Lafferty Maths Dept.

Created by Mr. Lafferty Maths Dept. Decimal Numbers Rounding to 1 decimal place Now try TJ2a Ex 4 Ch5 (page 46) www.mathsrevision.com 8-Jan-18 Created by Mr. Lafferty Maths Dept.

Created by Mr. Lafferty Maths Dept. Starter Questions www.mathsrevision.com 8-Jan-18 Created by Mr. Lafferty Maths Dept.

Created by Mr. Lafferty Maths Dept. Decimal Numbers 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. www.mathsrevision.com 2. Show all working. 8-Jan-18 Created by Mr. Lafferty Maths Dept.

Decimal Numbers 8 . 7 2 www.mathsrevision.com Add and Subtract Decimals When you add or subtract decimal numbers, it is important to line-up the decimal points. Example 1 : Calculate 7.8 + 0.92 www.mathsrevision.com 8 . 7 2 8-Jan-18 Created by Mr. Lafferty Maths Dept.

Decimal Numbers 3 . 1 6 www.mathsrevision.com 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 www.mathsrevision.com 3 . 1 6 8-Jan-18 Created by Mr. Lafferty Maths Dept.

Created by Mr. Lafferty Maths Dept. Decimal Numbers Add and Subtract Decimals Example 1 : Find the value x cm and y cm 3.91cm 2.1cm y cm 3.25cm 2.2cm x cm y cm www.mathsrevision.com x cm 6 . 0 1 1 . 0 5 8-Jan-18 Created by Mr. Lafferty Maths Dept.

Have you updated your Learning Log ? Decimal Numbers Add and Subtract Decimals Now try TJ2a Ex 5 Ch5 (page 48) www.mathsrevision.com Are you on Target ? I can ? 8-Jan-18 Created by Mr. Lafferty Maths Dept.