Subtraction With Decimals

Objectives

To subtract using the column method and to realise that decimal points do not affect how the calculation is carried out.

Resources

Abacus 4 Textbook 3 | Atlas or road map | Squared paper | Finding Change - Frog Method (YouTube)

Today's Lesson

Main Activity

For the mental warm up, find an atlas or road map with grid references marked on it. Select a town or place, then give your child the name of the place and the grid reference, giving the x-axis reference first.

Ask your student to find the place on the map.

Turn to page 66 in Abacus 4 Textbook 3 and look at the subtraction calculations with decimals.

Q1-4 are just like the questions from yesterday. Use Frog Method to calculate the change.

When solving Q5-8, explain to your student that these calculations will be set out in exactly the same way as with column subtraction.

Stress the importance of PUP (point under point) and then explain to your student that they can place the decimal point into the correct place for the answer before completing the calculation. They can then ignore the decimal point while the calculation is carried out and treat it as a normal column subtraction question.

For Example Q1 should be set out like this:


	5	1	.	6	8
-	2	7	.	8	8
			.

Complete the calculations on the page, regrouping wherever necessary.

Citations

[1] www.youtube.com