Page 45 - Whole Numbers (Addition and Subtraction)

11. Make five subtraction facts from each of the following facts.
(a) 1 000 − 600 = 400 (b) 1 000 − 500 = 500

(c) 1 000 − 800 = 200 (d) 1 600 − 600 = 1 000
(e) 1 600 − 1 000 = 600 (f) 3 400 − 400 = 3 000

12. Write the answers for the questions that you can do quickly.
Copy the number sentences for which you cannot give the
answers quickly.

(a) 3 100 − 500 = . . . (b) 4 500 − 300 = . . .

(c) 5 500 − 400 = . . . (d) 7 400 − 500 = . . .
(e) 8 500 − 800 = . . . (f) 8 100 − 800 = . . .

(g) 8 100 − 1 800 = . . . (h) 3 700 − 1 200 = . . .
(i) 7 200 − 500 = . . . (j) 7 200 − 700 = . . .

(k) 7 200 − 3 700 = . . . (l) 7 200 − 4 000 = . . .
(m) 7 200 − 4 100 = . . . (n) 7 200 − 4 200 = . . .

(o) 4 400 − 600 = . . . (p) 5 700 − 900 = . . .
(q) 9 300 − 800 = . . . (r) 5 700 − 1 900 = . . .

(s) 3 600 − 800 = . . . (t) 4 500 − 700 = . . .

When you cannot quickly find the answer for a simple
subtraction, you may think of another fact that may help you.
For example, when you cannot quickly find out how much
9 300 − 5 800 is, you may think of 9 300 − 6 000. If you know how
much 9 300 − 6 000 is, you know that 9 300 − 5 800 is 200 more.

13. Work on the sentences that you wrote down in question 12.
You can think of subtraction facts that you know. You can also
think of steps on the number line.

0 1 000 2 000 3 000 4 000 5 000 6 000 7 000 8 000 9 000 10 000

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