Cambridge Essentials Mathematics Core 8 N1.3 Homework

/ N1.3 Homework

1aWrite the first ten multiples of 3.

bWrite the first ten multiples of 4.

cWrite the numbers that are common multiples of 3 and 4.

dWhat is the lowest common multiple of 3 and 4?

2Find the lowest common multiple of each set of numbers.

a4,7b9,12c3,4,5

3aWrite one number which fits all threeof these statements.

It is a multiple of 6.

It is a multiple of 8.

It ends in ‘2’.

bExplain why a number which ends in ‘5’cannot be a multiple of 6.

4aWrite down all the factors of 24.

bWrite down all the factors of 40.

cWrite down the factors that are common to 24 and 40.

dWhat is the highest common factor of 24 and 40?

5Findthe highest common factor of each set of numbers.

a30,48b84,210c48,84, 132

6a11 has two factors:1 and 11. What type of number is 11?

bInvestigate the number of factors that each number from 1 to 20 has.

It may help you to use a table

like the one shown.

Comment on your results.

7 3, 6, 8, 9, 15, 24, 25, 32, 43, 72, 125

Write down two numbers from the list above which have these properties.

You can use a number more than once.

amultiples of 9

bfactors of 12

csquare numbers

dcube numbers

eprime numbers

8aCopy and complete this factor tree

bWrite 90 as a product of its prime factors.

9Use factor tree to write 126 as aproduct of its prime factors.

10aCopy and complete this table to find the prime factors of 264.

bCopy and complete:

264 = 

= 

11Use the dividing method shown in question 10to write 1008 as a product of prime factors.