Transcript Factors

Factors
9Y4
Tuesday 30th November
Finding factors
 Shade
on your number square each
time you see 36.
 How many times does 36 appear?
How can we use our number
square to help us find factors?
Any time the number you are
investigating appears in your number
square, the numbers that are
multiplying to make it are factors.
 The
numbers on your number square
that multiply to make 36 are:
3 and 12
4 and 9
6 and 6
So factors of 36 are: 3, 4, 6, 9, and 12
 Find,
using your number square, the
factors of:
10
Ways of making 10 by multiplying:
1 x 10
FACTORS OF 10 ARE: 1, 2, 5 AND 10
2x5
12
1 X 12
2X6
3X4
9
1X9
3X3
FACTORS OF 12 ARE: 1, 2, 3, 4, 6
AND 12
FACTORS OF 9 ARE: 1, 3, AND 9
 Use
you number square to help you
find ALL the factors of:
18
1 x 18
2x9
3x6
36
1 x 36
ALL THE FACTORS OF 18 ARE:
1, 2, 3, 6, 9 AND 18
2 x 18
ALL THE FACTORS OF 36 ARE:
3 x 12
1, 2, 3, 4, 6, 9, 12, 18 AND 36
4x9
6x6
Highest common factors
 List
all the factors of 36 and 24.
Look for the highest number that
appears in both lists.
This number is called the
highest common factor of
HCF for short.
Find the HCF of the following:
10 and 12
Factors of 10 = 1, 2, 5, 10
Factors of 12 = 1, 2, 3, 4, 6, 12
HCF = 2
18 and 24
Factors of 18 = 1, 2, 3, 6, 9, 18
Factors of 24 = 1, 2, 3, 4, 6, 8, 12, 24
HCF = 6
21 and 35
Factors of 21 = 1, 3, 7, 21
Factors of 35 = 1, 5, 7, 35
HCF = 7