Page 16 - E-Book prim 4

Delta Modern Language Schools

Primary stage
Maths Department

Prim 4 2024-2025

Unit (6): factors and multiple

Lesson 3 : Greatest common factor

Greatest common factor :

*Common factors of two numbers are factors that are the same

* The greatest common factor ( GCF ) of two numbers is the greatest
number that is a factor of both

EX: find the common factors ad GCF of 12 , 15

12 : 12 , 2 , 6 , 3 , 4 , 1

15: 15 , 3 , 5 , 1

Common factors: 1 , 3

G.C.F : 3

Relation between factors and multiples

Multiples of numbers and common multiplies : 5
5 X 0 = 0

5X 1 =5 5 x 2 = 10 5X 3 = 15 ……. Etc
0, 5 , 10 , 15 called multiples of 5

Write the multiplies of 4 , 6 up to 22 :

The multiple of 4 : 0,4, 8, 12, 16 , 20

The multiple of 6 : 0,6, 12, 18
The common multiplies are : 0 , 12

The Relation between factors and multiplies :

5 x 3 = 18

6, 3 are factors of 18
18 is multiple of 6 , 18 is multiple of 3

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