Subtraction Strategy Practise

• Place Value Strategy

Eg. 47 - 34 = 47 - 30 - 4

      = 17 - 4

      = 13

Or. 82 - 19 = 82 - 10 - 9

      = 72 - 9 (The nine is split into parts to make this step easier)

      = 72 - 2 - 7

      = 70 - 7

      = 63

• Equal Adjustment Strategy

(The second number in the equation is rounded up or down to a ‘tidy ten’, an equal amount must then be added or subtracted from the first number. NB In subtraction problems, you either add to both numbers OR subtract from both numbers)

Eg. 123 - 49 = 124 - 50

+1     +1 

       = 74

E.g. 84 - 52 = 82 - 50

-2   -2 

     = 32

- Reversibility Strategy 

(A subtraction equation can be reversed and made into an addition problem. A number line can then be used to help solve the problem)

Eg. 73 - 29 = ?

29 + ? = 73

29 30     70       73

    +1    +40      +3

29 + 44 = 73

so 73 - 29 = 44

Addition Strategy Practise

Have a go at these. Remember the same rules apply when you solve decimal problems, you just have to  make sure you are using the right place value columns.
You can choose which strategy you would like to use, but use all of the different strategies at some stage.

1)    34 + 78 =

2)    359 + 102 =

3)    3.8 + 6.9 =

4)    57 + 88 =

5)    23.7 + 12.4 =

If you have finished these, ask someone at home to write some similar problems for you to solve.
Ask if you get stuck!

Addition Strategy Revision

Today we revised the 3 key addition strategies. They are:

• Place Value Strategy

(Numbers are separated into the tens and ones)

Eg.    45 + 13 = (40 + 10) + (5 + 3)

                        = 50 + 8

                        = 58

- Advanced Place Value Strategy - Holding the biggest number

Or. 57 + 47 = 57 + 40 + 7

                   = 97 + 7

                   = 104

• Rounding and Compensating Strategy

(One of the numbers is rounded up or down to a ‘tidy ten’, an equal amount must then be taken away or added to the other number in the equation to balance it. NB: In addition problems you use two different actions addition/subtraction)

Eg. 63 + 59 = 62 + 60

-1     +1  

                    = 122

Percentages Practise

Percentages       Per = out of      Cent = 100

Draw and record your solutions. Try showing your thinking on the double number line

From Numeracy Book 7 pages 53 - 60 – Hot Shots

Challenge A Rachel bought a dress which was $84 but was discounted by 20%. How much did she pay for the dress?                                                                                                          $84                                                                                                           100%

Challenge B Terina gave away 24 lollies which was 30% of her lollies in the jar. How many did she have in the jar originally? How many did she have left?                                                                                                                                                                                                                    100%

Challenge C Ronny took 30 shots at goals. He got 25 kicks over. What was his kicking percentage?                                                                                                                                                                                                                    100% ·      Try 30 shots and only 8 over ·      Make up your own percentage question to try to solve on the double number line

Improper fractions

Rename the following fractions to mixed numbers and place these on a number line.

9/2                   14/3                      16/5

Fractions Practise Activities

Birthday Cakes – from FIO Baffling Braids to Crazy Cakes!! 

Number Book 2, Level 3

Challenge A Nicole is decorating her birthday cake using red and yellow jelly beans solve the following three problems using the ‘cut out rectangle frames’ 1.    If ¼ = red and the rest are yellow what proportion of the jelly beans are yellow? 2.    If there are a total of 20 jelly beans on the cake, how many red and yellow beans are there? 3.    Nicole made another birthday cake using the same proportions of red and yellow beans. There were 7 red beans. How many beans would there be altogether? How many would be yellow?

Challenge B Using the rectangle shapes only solve this problem There is a third of a birthday cake left over. Moana and Henri want a half of it each. What fraction will they get? Try solving the same problem using the beans [jelly beans] if there was 24 beans spread over the whole cake. What would half of a third be? ½ x ⅓ of 24 beans Draw and record your thinking

Challenge C Tia is decorating her birthday cake using red, yellow and blue jelly beans 1.    If ½ = red, 1/3 = yellow and the rest are blue what proportion of the beans are blue? Use different colour strips to show the half and third on the ‘cut out rectangle frames’. [You might want to arrange the ‘thirds’ strips going horizontal and the ‘half’ strip going vertical] 2.    If there are a total of 24 beans on the cake, how many red, yellow and blue beans are there? 3.    Tia made another birthday cake using the same proportions of red, yellow and blue beans. There were 9 red beans. How many beans were there altogether? How many yellow and blue beans were there? Draw and record your thinking

You could laminate and cut out the three challenges and give the challenge tasks A, B, & C separately at each maths lesson to allow for plenty of student discussion