Year 4 Gorillas Term 2 Unit 10

Day 1

L.O.1

To be able to derive quickly two-digit pairs that total 100

To add several two-digit numbers

Different numbers will be shown. Your job is to write the complement to 100.

30 60 20

90 35 75

15 45 75

5 65 85

Quickly copy this number grid into your books

Do these:

1. Which number is nearest 100?

2. Which pair of numbers total 100?

3. What is the sum of the top row?

4. What is the sum of the bottom corners?

5. What is the total of the middle column?

6. Add the bottom row.

7. Sum the diagonal from the top left.

8. Total the numbers under 40.

9. Add the two highest numbers.

10. Find the sum of the left-hand column.

L.O.2

To be able to extend written methods to column addition of two integers less than 10 000

3587 purchased advance tickets for the final home game of the season at Boston United. A

further 675 people bought tickets on the gate. How many people attended the game altogether?

Q. What calculation do we need to do to work out the answer to this problem.

The calculation is addition.

REMEMBER …

This is the COLUMN method of addition:

468 468

468+276 + 276 + 276

400 + 200 = 600 600 14

60 + 70 = 130 130 130

8 + 6 = 14 14 600

744 744 744

We’ll do this in the same way but add the most significant digits first.

3 5 8 7

+ 6 7 5

Q. How many thousands will there be? 3 0 0 0

Q. How many hundreds will there be? 1 1 0 0

Q. How many tens will there be? 1 5 0

Q. How many units will there be? 1 2

Q. What is the total? 4 2 6 2NOTICE : THE FIGURES ARE IN STRAIGHT COLUMNS!

Do these using the COLUMN method and starting with the most significant digit.

Keep your digits in straight columns.

1. Imelda Marcos bought 2356 pairs of shoes in 1998 and 947 pairs the following year. How many pairs of shoes had she altogether?

2. Prince Charles owns 8894 acres of land in Cornwall and 658 acres in Norfolk. How much land has he?

3. When Granny sold the last of her jewels she made £2486. Her jewel sale last year brought her £828 and the year before that £593. How much did she make altogether?

We’ll do this one together:

5709 + 3296

Let’s try this but begin with the least significant digit.

4736 + 582

4 7 3 6

+ 5 8 2

8

1 1 0

1 2 0 0

4 0 0 0

5 3 1 8

Do this. Use either method but be prepared to explain your reasoning.

6285 + 445

By the end of the lesson the children should be able to :

Use a written column method to add a

four-digit to a three-digit number by adding the most significant digit first

or the least significant digit first.

Discuss, explain and compare methods.

Year 4 Gorillas Term 2 Unit 10

Day 2

L.O.1

To be able to count on and back in equal steps.

To use known number facts and place value for mental addition.

We are going to count on and back in steps of 0.1 beginning at different points from 0 to 1

1

0

We are going to count on and back in steps of 0.1 beginning at different points from 1 to 2

2

1

We are going to count on and back in steps of 0.2 beginning at different points from 0 to 2

2

0

We are going to count on and back in steps of 0.5 beginning at different points from 0 to 5

5

0

1.2 0.6 2.7 3.3

0.8 0.2 4.4 3.8 6.1

Find a pair of numbers which add to :

1, 2, 4, 5, 6

.

2.5 5.4 1.2 1.8

2.7 3.5 1.5 6.8 2.3

6.6 3.4 1.9 4.5 4.2

Find three numbers which make:

6, 7, 10

1.8 1.9 2.3 2.5 2.7 1.8 1.2 3.4 5.4

.

2.5 5.4 1.2 1.8

2.7 3.5 1.5 6.8 2.3

6.6 3.4 1.9 4.5 4.2

Find four numbers which make:

12, 13

1.5 2.5 3.5 4.5 6.8 1.2 2.3 2.7

L.O.2

To be able to use column written methods to add two or more decimals.

Last week I spent £48.76 at the supermarket.

This week I spent £37.53.

How much did I spend altogether?

Q. What calculation do we need to carry out?+

Q. How could we work this out?

Q. What would you estimate the answer to be?

We shall use a similar written method of addition to that used in the last lesson.

4 8.7 6 3 7.5 3

7 0.0 0 1 5.0 0 1.2 0 0.0 9

8 6.2 9Q. Does this answer seem reasonable?

Let’s try this one.

We shall begin by adding the least significant digit. Your assistance is required!

14.78 m. + 26.24 m

Where shall we start?

You will be given a worksheet to do.

Begin each problem by adding the

least significant digit.

REMEMBER :

ESTIMATE B4U CALCULATE

At the Funfair the rides are priced as follows:

White Knuckle £1.65

Dodgems £0.90

Wall of Death £2.30

Space Wheel £1.25

1. How much is it to go on each ride once?

2. If I have £4.00 to spend which rides could I go on?

3. How much does it cost to go on the Space Wheel three times and the White Knuckle twice?

4. Granny is afraid of the Dodgems but likes all the other rides. How much does she spend if she goes on each one twice?

By the end of the lesson the children should be able to:

Use a written column method to add two or more decimal numbers;

Know that a decimal points should link up under each other;

Solve mathematical problems involving money and measures.

Year 4 Gorillas Term 2 Unit 10

Day 3

L.O.1

To have a rapid recall of multiplication facts.

Let’s say our tables (twice) :

6x 8x 9x

and answer some questions about them.

Answer the questions using number fans.

Now ask your partner to recite the same

tables and then ask them questions.

5 minutes

Do these:

7 x 8 = 5 x 6 = 8 x 8 =

8 x 9 = 7 x 6 = 9 x 5 =

70 x 8 = 0.5 x 6 = 800 x 8 =

8 x 0.9 = 70 x 60 = 0.9 x 0.5=

L.O.2

To be able to subtract whole numbers

with up to four digits using a written

column method.

3450 people attend a football match. At half time 867 people leave. How many people stay to the end of the match?

Q. What calculation must we carry out to work out the answer?

-

Q. How could we estimate the answer?

Q. What is a sensible estimate?

2500

Remember the complementary addition method used to work out the answer to a problem?

867 900 1000 3000 3450

+33 +100 +2000 +450

The jumps are to and from 100’s and 1000’s as this helps make the addition easier.

Is the answer ( 2583 ) close to the estimate of 2500 ?

The sum can be set out using the column method.

867 900 1000 3000 3450

+33 +100 +2000 +450

3450

- 867

33 to make 900

100 to make 1000

2000 to make 3000

450 to make 3450

2583 Answer is 2583 c.f. the estimate of 2500

2340 - 758

Q. What calculation must we carry out to work out the answer?

Q. How could we estimate the answer?

Q. What is a sensible estimate?

1500

Remember the complementary addition method used to work out the answer to a problem?

758 800 1000 2340

Is the answer ( 1582 ) close to our estimate?

+42 +200 +1340

The sum can be set out using the column method.

758 800 1000 2340

+42 +200 +1340

2340

- 758

42 to make 800

200 to make 1000

1340 to make 2340

1582 Answer is 1582 c.f. the estimate of 1500

Try these with a partner. Agree an

estimate before B4U calculate.

ALL 1. 832 - 645

2. 733 - 1609

3. 8976 - 543

4. 573 - 67

PRISMS 5. 6571 - 89

6. 4773 - 882

3450 - 867 = 2583

Q. What is the answer to 2583 + 867?

Why?

Q. Is there a connection between addition and subtraction? If so, what is it?

Does the same rule apply here?

30 – 10 = 20 : 20 + 10 = ____

88 – 36 = 52 : 52 + 36 = ____

45 – 18 = 27 : 27 + 18 = ____

76 – 42 = 35 : 35 + 42 = ____

Copy and complete :

2733 – 1609 = 1124 : 1124 + 1609 = _____

By the end of the lesson the children should be able to:

Subtract pairs of numbers involving a different number of digits by counting up;

Find an estimate and check answers;

Use the relationship between addition and subtraction to check answers