How_To_Be_Good_At_Math

22 NUMBERS •^ ORDERING NUMBERS

Ordering

numbers

Sometimes we need to compare a whole series

of numbers so that we can put them in order.

To do this, we use what we know about place

values and significant figures.

First, we put the candidates’ votes

into a table so we can compare the

place value of their most significant digits.

Cybertown has held

an election for mayor.

We need to put the

candidates in order of

the votes they received.

Let’s look at the most significant digits. Only

Krog’s total has a digit in the ten thousands

column. So, his vote total is the highest and we

can put it first in a new table.

When we compare second significant digits,

we see Moop and Jeek have the same digit in

the thousands. So, we compare third significant

digits. Moop’s digit is greater than Jeek’s.

We carry on comparing digits in the

place-value columns until we have put

the whole list in order, from largest to smallest

numbers. Krog is the new mayor!

Xoon

912

votes

The first

significant

figure is the

one furthest

to the left

ThTTh H T O

10423

5234

5121

912

444

45

Krog

Moop

Jeek

Xoon

Flug

Zeet

Zeet

45

votes

ThTTh H T O

10423

5234

5121

Krog

Moop

Jeek

ThTTh H T O

Krog^10423

ThTTh H T O

912

45

5234

444

10423

5121

Xoon

Zeet

Moop

Flug

Krog

Jeek

VOTE

KROG!

022_023_Ordering_Numbers.indd 22 29/02/2016 14:08