Addition and Subtraction Addition Relate addition to combining




























- Slides: 28

Addition and Subtraction

Addition Relate addition to combining two groups and counting on and record in a number sentence using + and = signs. 13 + 24 = 37 Record addition by: model and images +

Your turn • 23 + 26 =

When the children are comfortable with this we move onto adding on a number line. 13 + 24 = 37 +10 13 23 +1 34 +1 35 +1 36 37

Your turn • 32 + 25 =

From this we move onto using partitioning both numbers. 35 + 23 30 + 20 = 50 5+ 3=8 50 + 8 = 58

Your turn 43 + 56 =

Develop methods for adding two digit and three digit numbers by partitioning second number only. 246 + 37= 246 + 30 = 276 + 7 = 282

Your turn • 145 + 54 =

Then we develop written methods for addition of two and three digit numbers using expanded methods of recording. 375 + 67 300 + 70 60 300 130 5 7 12 = 442

How can we apply this knowledge?

Problem solving T= Target I= Information N= Number sentence A=Answer

Mina and Ben play a game. Mina scores 70 points. Ben scores 42 points. How many points did they score in total? T= How many points did they score in total? I = 70 42 + N= 70 + 42 = A=

Your turn Mina and Ben play a game. Mina scores 35 points. Ben scores 63 points. How many points did they score in total? T= I= N= A=

There are 265 children at Hill School. 102 children have a packed lunch. 27 children go home for lunch. The other children have a school lunch. How many children have school lunch?

Subtraction Relate subtraction to taking away by counting back and as counting on and record in a number sentence using the – and = signs.

Subtraction not crossing through the tens boundary. 46 – 25 = - 25 = 21 In a subtraction calculation we always write the digits of the second number, we don’t draw the image!

Subtraction crossing the tens boundary. 53 – 27= - 27 = 26

Your turn Have a go, using models and images at these two calculations. 1. ) 57 - 32 = 2. ) 42 – 16 =

Once the children are comfortable with this strategy we move them onto subtraction on a number line. 49 – 14 = -1 35 -1 36 -1 37 - 10 -1 38 39 49

Your turn 56 – 38 =

Subtraction by partitioning not crossing the tens boundary. 48 – 32 = 40 – 30 = 10 8 - 2 = 6 10 + 6 = 16

Subtraction crossing the tens boundary using partitioning. 53 – 37 = 50 – 30 = 20 10 3 - 7= We can’ t do this so we take one of the above tens. 13 – 7 = 6 10 + 6 = 16

Partitioning only the second number. 78 – 43 = 78 – 40= 38 38 - 3= 35

This is the same process even when crossing through the tens barrier. 63 - 28 = 63 - 20 = 43 43 - 8= 35

Begin to record calculations in preparation for an efficient standard method- expanded decomposition. 81 - 57 70 and 11 50 and 7 20 and 4 = 24

Problem Solving Sita had 87 p. She spent 35 p. How much money did she have left? T= How much money did she have left? I = 87 p 35 p left - N= 87 p – 35 p= A=

There are 104 children at Delton School. 48 children are girls. How many are boys? T= How many are boys? I= 104 48 - N=104 - 48 A=
Relate addition and subtraction
Now you try clipart
6-3 elimination using addition and subtraction
Solving equations using addition and subtraction
Subtraction properties
Adding decimal rules
Addition and subtraction of hexadecimal numbers
6-3 elimination using addition and subtraction
Add 3-digit number to 2-digit games
Addition and subtraction of hexadecimal numbers
Column addition
Solving addition and subtraction equations answers
Addition and subtraction with signed magnitude data
Trig addition and subtraction
Are mixed numbers rational numbers
Rational numbers addition and subtraction
Integers adding and subtracting calculator
6-3 elimination using addition and subtraction
Solving addition and subtraction equations
Solve the system of equations using subtraction.
Addition subtraction and multiplication of polynomials
Color addition and subtraction
Addition scientific notation
Add and subtract key words
To add two numbers having the same sign find the
Addition and subtraction property of inequality
Solving inequalities using addition and subtraction
White rose year 2 addition and subtraction
Addition property of equality