﻿ Unit 2 Section 1 : Place Value

# Unit 2 Section 1 : Place Value

This section deals with the revision of place value.

Remember that we write decimal numbers in the form:

 Thousands Hundreds Tens Units . Tenths Hundredths Thousandths

## Example 1

Here are some number cards:

 1 7 3 5

You can use each card once to make the number 1735, like this:

 1 7 3 5
 (a) What is the biggest number you can make with the four cards?
 (b) Explain why you cannot make an even number with the four cards.
 Note: It is often helpful to refer to a number line when comparing values; a number line can also show negative values:
Remember that the symbol < means 'less than' and > means 'greater than'.

## Example 2

Put the correct sign, < or = or >, into each sentence.

 (a) – 7 – 2 (b) 3 – 2 – 5 (c) 3 – 5 4 – 6

## Example 3

The arrow on this thermometer shows a temperature of 10 °C.

(a)Draw an arrow on the thermometer to show
a temperature of 24 °C.
Label the arrow 24 °C.
(b)Draw an arrow on the thermometer to show
a temperature of – 4 °C.
Label the arrow – 4 °C.
(c)The temperature was – 10 °C.
It went up 15 °C.
What is the temperature now?
(d)Write these temperatures in order, coldest first.
 3 °C, – 10 °C, 0 °C, 20 °C, – 1 °C

## Exercises

Work out the answers to the questions below and fill in the boxes. Click on the button to find out whether you have answered correctly. If you are right then will appear and you should move on to the next question. If appears then your answer is wrong. Click on to clear your original answer and have another go. If you can't work out the right answer then click on to see the answer.
Question 1
 (a) Write the numbers: (i) one hundred and eighty, (ii) two hundred and twelve, (iii) one hundred and eight, (iv) ninety two (b) Using the numbers in (a), write them in order with the smallest first. , , ,
Question 2
Ali drew a picture to show what there is above and below the sea at Aber.

The anchor is at about – 40 m.

 (a) What is at about +10 m ? - choose - Hotel Bird Boat Diver Fish Anchor Chest (b) What is at about –10 m ? - choose - Hotel Bird Boat Diver Fish Anchor Chest (c) What is about 30 m higher than the chest? - choose - Hotel Bird Boat Diver Fish Anchor Chest
Question 3
Put the correct sign, < or = or >, into each number sentence, to make it correct.
 (a) 8 + 2 7 + 6 (b) 6 – 3 1 + 2 (c) 0 – 3
Question 4
Write the following sums of money in pounds, in decimal form.
 (a) Seventy two pounds, forty five pence. (b) One hundred and three pounds, fifty pence. (c) One hundred and thirty pounds, five pence.
Question 5
Here are some number cards:
 5 0 7 1
 (a) What is the largest possible number you can make, using all four cards? (b) What is the smallest possible number, using all four cards but starting with a non-zero digit? (c) What is the smallest possible number you can make, using only three of the cards and starting with a non-zero digit?
Question 6

(a) Look at this part of a number line:

Complete this sentence:
The numbers on this number line go up in steps of .
(b) This is a different number line.

What are the 3 missing numbers?

(c) This is a different number line.

What are the 3 missing numbers?

(d) This is a different number line.

What are the 2 missing numbers?

Complete this sentence:
The numbers on this number line go up in steps of .
(e) This is a different number line.

What are the 3 missing numbers?

Complete this sentence:
The numbers on this number line go up in steps of .