How_To_Be_Good_At_Math

102 CALCULATING •^ COUNTING IN MULTIPLES

Counting in multiples

When a whole number is multiplied by another whole number,

the result is called a multiple – we looked at multiples on

pages 30-31. When we’re doing multiplication calculations,

it helps to know how to count in multiples.

Add 2 each

time

Add 6 each

time

Counting in 3s

This number line shows the numbers

we get when we start to count in multiples

of three from zero. The fifth jump takes us

to 15, so 3 × 5 = 15

Counting in 2s

Look at this number line. It shows the

numbers we get when we count up in twos

from zero. Each number in the sequence is

a multiple of 2. For example, the fourth jump

takes us to 8, so 2 × 4 = 8

Counting in 6s

Now look at this number line. It shows us

the first few multiples of six. The third jump

takes us to 18, so we can say that 6 × 3 = 18

Counting in 8s

This number line shows us the first three

multiples of 8 when we count up from zero.

The second jump takes us to 16, so 8 × 2 = 16

These number lines show us the first

few multiples of 2, 3, 6, and 8. Learning

to count in multiples will help us with other

multiplication tables, which we’ll look at on

pages 104-105.

0 4321 5 6 7 8 9

0 4321 5 6 7 8 9

0 321

0 4321 5 6 7 8

+3 +3

+8

+6

+2 +2

2 × 1 = 2 2 × 2 = 4

3 × 1 = 3 3 × 2 = 6

6 × 1 = 6

8 × 1 = 8

102_103_Counting_in_multiples.indd 102 29/02/2016 18:56