Numbers and the number system
More and less
Solving mathematical problems
Challenge
Ordering numbers
Numbers and the number system
Solving mathematical problems
Challenge
Write an addition or subtraction calculation for each of these statements. 40 more than 6472 is 6512.
500 more than 4791 is 5291.
3000 less than 9465 is 6465.
600 less than 2351 is 1751.
70 less than 298 is 228.
0
8000 more than 1506 is 9506.
4
What patterns do you notice?
Look at the cards above.
What generalisations can you make when adding or subtracting a multiple of 10, 100 and 1000?
Write numbers for each of the blank cards so that the seven numbers are in order.
Think about … • • •
Think about what changes and what remains the same when you add or subtract a multiple of 10, 100 or 1000.
Remember: the multiples of 10 are 10, 20, 30, … 90. the multiples of 100 are 100, 200, 300, … 900. the multiples of 1000 are 1000, 2000, 3000, … 9000.
Each of the numbers in the box is either the sum of, or difference between, two of the numbers outside the box. Write the addition or subtraction calculation for each of the numbers in the box.
How many different ways can you think of?
Think about … Recording your results carefully will help you to spot any patterns.
Work systematically to find all the different ways. Which numbers will stay the same and which numbers will change?
What if ?
What if ?
70
9182 5000 4937 600 7748
4635 4872 2000 2748 60 6281
7635 8047 9252
8281 400 2306 8
–3
–6
90
1506 3000 5537 4932 3231 800 3631 7957
What if you use these numbers instead?
–10 When you’v e finished, tur n to page 80.
–5
–2
3 When you’v e finished, tur n to page 80. 9