# Castle Douglas Primary and Early Learning and Childcare Centre # Multiplication and Division

Activity 1 – The Answer is 2400

Focus – I can recall my table facts quickly and accurately and can use multiples of 10 and 100 to create new facts.

Resources – pencil and paper

Write as many multiplication questions as you can involving multiples of 10 and 100 with the answer 2400,  e.g.
3 × 800, 40 × 60,
12 × 200, 80 × 30,
120 × 20,
400 × 6, etc.

Also try using more than two numbers in the multiplication questions, e.g.
3 × 40 × 20 or
2 × 20 × 60 or
2 × 2 × 2 × 300, etc. Activity 2 – Funny Puzzles

Focus – I can work with the four operations using a variety of strategies to solve calculations.

Resources – pencil and paper

Make calculation puzzles using numbers of things personal to you, e.g. What is the number of doors in your house, multiplied by your favourite number and then divided by your age? Make up and calculate answers to four different puzzles and ask other family members to solve them. Activity 3 – Kilometres to Metres

Focus – I can multiply and divide by 1000.

Resources – atlas, internet e.g. Google maps, pencil and paper.

Find distances in kilometres between towns or cities (either direct distance or driving distance), from an atlas or internet. Write the distances in kilometres and then convert them to metres (by multiplying by 1000), e.g. London to Edinburgh is 535 km = 535 000 m. Activity 4 – Money Grabbing

Focus – I can create a set of multiples and find common multiples between tables.

Resources – several 1p, 2p, 5p and 10p coins, pencil and paper

Collect a pile of small coins (about four 10p coins and some 1p, 2p and 5p coins). Grab some of the coins and write how much has been grabbed, e.g. 38p. If this is a multiple of 2, 3, 4, 5, 6, 7, 8, 9 or 10 you score a point for each, e.g. 24p would score 5 points (it is a multiple of 2, 3, 4, 6 and 8), but 17p would score no points. Activity 5 – Prime Shirt Numbers

Focus – I can work out factor pairs and work out which numbers are prime.

Resources – pencil and paper, internet access or sports information.

Investigate which players in your favourite sports team wear prime numbers on their shirts. Activity 6 – Halving Chains

Focus-I can use doubles, near doubles and halves to help me in my calculations.

Resources – pencil and paper

Take each of the following numbers and keep halving until a number ending in 5 is reached: 8000, 1280, 1040, 1240, 1440, 1360.
Which number has the longest chain?    Which number has the shortest chain?
Answers are at the bottom of the page. Activity 7 – Which is Largest? (TU)

Focus – I have extended my range of mental strategies for multiplication – Rounding and adjusting.

Resources – pencil and paper

Work out and discover which of the following four calculations has the largest answer. Predict first and then use an appropriate method to perform each calculation.

17 × 8
19 × 6
21 × 4
22 × 9

Answer at the bottom of the page. Activity 8 – Choose Your Digits.

Focus – I can work out and record my multiplication calculations in a variety of different ways – Grid method (2-digit × 1-digit and 3-digit × 1-digit).

Resources – pencil and paper

Choose a set of three (or four) different digits and arrange them to make six different 2- or 3- digit × 1-digit multiplication questions,
e.g. 5, 6 and 7 (and 8) would make questions such as 56 × 7,     65 × 7,      75 × 6, etc  (or 576 × 8,     768 × 5,     785 × 6, etc).
Solve each question and find which has the largest answer. Activity 9 – Which is Largest? (HTU)

Focus – I can work out and record my multiplication calculations in a variety of different ways – Formal methods (2-digit × 1-digit and 3-digit × 1-digit).

Resources – pencil and paper

Work out and discover which of the following four calculations has the largest answer:
351 × 6
225 × 9
289 × 7
389 × 5
Predict first and then perform each calculation to find out which has the largest answer. Activity 10 –  Choose Your Digits

Focus – I can work out and record my multiplication calculations in a variety of different ways – Grid method and formal methods (2-digit × 2-digit and 3-digit × 2-digit).

Resources – pencil and paper

Choose a set of four (or five) different digits and arrange them to make six different 2- or 3- digit × 2-digit multiplication questions,
e.g. 4, 5, 6 and 7 (and 8) would make questions such as
56 × 47,      65 × 74,      75 × 46, etc (or 576 × 48,       764 × 85,      785 × 64, etc).
Solve each question and find which has the largest answer. Activity 11 – What Remains? (A)

Focus – I can work out and record my division calculations in a variety of different ways – Chunking method (2-digit ÷ 1-digit).

Resources – pencil and paper

Find which numbers between 60 and 90 have a remainder of 3 when divided by 6, 7 or 8.  Answers are at the bottom of this page. Activity 12 – Two to Ten

Focus – I can work out and record my division calculations in a variety of different ways – Expanded method (2-digit ÷ 1-digit, 3-digit ÷ 1-digit, 2- and 3-digit ÷ multiple of 10).

Resources – pencil and paper

Choose a 2-digit number between 50 and 100, e.g. 73 and divide it by all the numbers from 2 to 10, using whichever method you prefer. Activity 13 – Digit Dilemmas

Focus – I can work out and record my division calculations in a variety of different ways – Formal method (2-digit ÷ 1-digit and 3-digit ÷ 1-digit).

Resources – pencil and paper.

Write all six 3-digit ÷ 1-digit questions that can be written using the digits 4, 5, 6 and 7, e.g. 456 ÷ 7, 674 ÷ 5, 647 ÷ 5

Guess which question will have the largest answer and then work out the division sums to find out if you are correct. Activity 14 – What Remains? (B)

Focus -I  can work out and record my division calculations in a variety of different ways – Formal method (2-digit ÷ 1-digit and 3-digit ÷ 1-digit).

Resources – pencil and paper.

Find which 3-digit numbers with three identical digits e.g. 111, 222, 333, etc have a remainder of 5 when divided by 9. Activity 15 – Divisions, Divisions.

Focus – I can work out and record my division calculations in a variety of different ways – Formal method using sharing (2-digit ÷ 1-digit and 3-digit ÷ 1-digit).

Resources – paper and pencil

Choose any 3-digit number, e.g. 793 and divide it by each number from 3 to 9 using an appropriate method.  Ask a family member to check your answers. Try again with as many different numbers as you like. 