Page 6 - Whole Numbers (Addition and Subtraction)
P. 6
7. Show how 15 + 8, 35 + 8, 17 + 7 and 46 + 9 can be calculated by
filling up to tens.
8. The number line diagrams below show how you could be
thinking when you are calculating 8 + 7, 6 + 7 and 8 + 9. Use
arrows as shown on the previous page to show the same thinking.
(a) + 7
0 8 10 15 20
(b) + 7
0 6 10 20
(c) + 9
0 8 10 20
You can see on this number line that 8 + 6 = 14.
8 units 6 units
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
You can also see that 14 − 8 = 6, and 14 − 6 = 8.
9. Which addition fact, and which two subtraction facts can you
see on each number line below?
(a)
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
(b)
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
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