Maths HomeWork :D

Textbook p9 #25:

The Prime factorisation of a number is 2^4 X 3^5 X 7^2 X 11.

Write down 3 factors of the number that are greater than 100.

(Hint: 16 X 11 = 176, which is a factor.)

2x2x2x2=16

3x3x3x3x3=243

7x7=49

11=11

16x49=784 ( 1st factor )

49x11=539 ( 2nd Factor )

since 3x3x3x3x3=243 , it is the last factor. otherwise 243x11=2673 ( 3rd factor )

Textbook p9 #26:

The Prime factorisation of two numbers are 2 X 3^2 X 7^3 X 13 and3 X 7^2 X 13^3 X 17 .

Write down 3 common factors of the numbers.

First Number:

2x(3x3)x(7x7x7)x13=80262

2|80262

3|40131

3|13377

7|4459

7|637

7|91

13|13

_1_

2nd number :

3x(7x7)x(13x13x13)x17=5490303

3	5490303
7	1830101
7	261443
13	37349
13	2873
13	221
17	17
	1

the common factors are 3, 7 and 13.