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Building NumberPlace Value
You are going to recap or learn:
How to read and write large numbers written in digits.How to compare and order whole numbers.
What skills should you have already?
You need to be able to read, write and compare numbers up to 999.
What’s It All About?
Read these numbers:
980
The position of each digit in the number makes a difference to its value.
Nine hundred and eighty908 Nine hundred and eight98 Ninety eight
Recap on Place Value
As the place value changes the number
changes...
Recap on Place ValueRemember – the position of a digit changes its value!Digits are grouped in threes...
Read these numbers.
ThousandHundred
s Tens Units Hundreds Tens Units
3 5 13 2 7 0 9
7 5 6 1 5 0
The decimal number system is based on the number 10…
Recap on Place ValueNumbers don’t just “happen” - they have structure!
1 ten = 10 units1 hundred = 10 tens1 thousand = 10 hundreds and so on ...
ThousandHundred
s Tens Units Hundreds Tens Units
3 5 13 2 7 0 9
7 5 6 1 5 0
10 of these makes
1 of these
10 of these makes
1 of these
10 of these makes
1 of these
10 of these makes
1 of these
10 of these makes
1 of these
Recap on Place ValueIf there are more digits, the table needs more columns...
Read these numbers.
Million ThousandHundreds Tens Units Hundreds Tens Units Hundreds Tens Units
2 4 1 2 3 0 5
1 4 0 3 0 8 1 0
1 5 2 6 2 1 0 0 0
Digits on the left are worth more than digits on the
right.
Write this number in digits.
Six hundred and two thousand five hundred and ninety.
Writing a number in digits is easy if you picture the place value table:
Writing Large Numbers
ThousandHundred
s Tens Units Hundreds Tens Units
6 0 2 5 9 0
4. Two million, three hundred thousand and seventy seven.
3. Seventeen thousand and thirty five.
2. Ninety one thousand six hundred and twenty one.
1. Four hundred thousand one hundred and sixty six.400 166
91 621
17 035
2 300 077
Your Turn
5. Ten million, seventy one thousand four hundred and two. 10 071 402
Comparing/Ordering NumbersWrite the numbers in the correct order of size.Start with the smallest.
49 562 235 280 7 320 1 253 762
49 562235 280
7 320
1 253 762 The 4-digit number is smallest...
235 280
Comparing/Ordering NumbersWrite the numbers in the correct order of size.Start with the largest.
349 562 235 280 394 320 253 762
349 562394 320
253 762All the numbers have 6
digits, so compare from the left ...
Your TurnWrite the numbers in the correct order of size.Start with the smallest.
1. 99 562 135 980 8 320 7 253 762
2. 35 565 71 623 19 819 17 368
3. 4 793 162 4 703 762 4 910 724
4. 1 703 762 805 122 851 724
8 320 99 562 135 980 7 253 762
17 368 19 819 35 565 71 623
4 703 762 4 793 162 4 910 724
805 122 851 724 1 703 762
Recall the place value table...
Multiplying Integers by 10, 100 etc
ThousandHundred
s Tens Units Hundreds Tens Units
55 0
5 0 05 0 0 0
5 0 0 0 05 0 0 0 0 0
10 10 10 10 10
Multiplying Integers by 10, 100 etcThousand
Hundreds Tens Units Hundred
s Tens Units
55 0
5 0 05 0 0 0
5 0 0 0 05 0 0 0 0 0
The zeros act as placeholders making sure the 5 is in the correct place value each time...
To multiply by 10, one place-holding zero is needed.
How many place-holding zeros are needed to multiply by 100?
How many place-holding zeros are needed to multiply by 1000?
Is there a pattern?
Multiplying Integers by 10, 100 etc
Two
Three
Again recall the place value table...
Dividing Integers by 10, 100 etc
ThousandHundred
s Tens Units Hundreds Tens Units
2 0 0 0 0 02 0 0 0 0
2 0 0 02 0 0
2 02
10 10 10 10 10
Dividing Integers by 10, 100 etcThousand
Hundreds Tens Units Hundred
s Tens Units
2 0 0 0 0 02 0 0 0 0
2 0 0 02 0 0
2 02
The place-holding zeros are removed each time the number is divided by 10 to move the 2 to the correct place value...
To divide a number that has place-holding zeros on the right by 10, one place-holding zero is removed.
How many place-holding zeros must be removed to divide by 100?
How many place-holding zeros must be removed to divide by 1000?
Is there a pattern?
Dividing Integers by 10, 100 etc
Two
Three
Your TurnWork out.
1. 34 000 10
2. 3 554 100
3. 793 162 10
4. 1 703 700 100
= 3 400
= 355 400
= 7 931 620
= 17 037
To divide a number that has place-holding zeros on the right by 10, one place-holding zero is removed.
What if the number does not have any place-holding zeros to remove?
Dividing Integers by 10, 100 etc
End
