Square Prime number Multiple of 3 Factor of

Square Prime number Multiple of 3 Factor of 12 Fill each cell with a number between 1 and 20 so that they follow the rules for the rows and columns. Factor of 45 Consecutive numbers Numbers may not be repeated

Square Prime number Multiple of 3 Factor of 12 4 3 12 Factor of 45 9 5 15 Consecutive numbers 16 17 18

240 cm 180 cm This is the floor plan of a new classroom. The school want to tile the floor with square tiles. What size tiles could the school buy if they want the tiles to cover the floor exactly, without cutting any or without any gaps?

240 cm 180 cm What are all the different sized square tiles we can use? These numbers are all common factors of 240 and 180.

Today we are going to look at common factors Write down the factors of 24 1, 2, 3, 4, 6, 8, 12, 24 Write down the factors of 36 1, 2, 3, 4, 6, 9, 12, 18, 36 Which factors are common to both? Which factor is the Highest Common Factor?

In your books: Title: Highest Common Factor Find the Highest Common Factor (HCF) of these pairs of numbers: 1. 12 and 16 4 2. 15 and 30 15 3. 6 and 18 6 4. 8 and 21 When the HCF = 1, the numbers 1 are said to be coprime

When the numbers are large: Find the Highest Common Factor of 240 and 180 240 180 10 24 18 2 12 9 3 4 3 Find any common factor > 1 Divide both numbers by the factor Repeat until the numbers are coprime

When the numbers are large: Find the Highest Common Factor of 128 and 144 128 144 2 64 72 2 32 36 2 16 18 2 8 9

In your books: Find the Highest Common Factor (HCF) of these pairs of numbers: 1. 162 and 90 18 2. 135 and 105 15 3. 240, 180 and 150 30 4. 675 and 1575 225