Q.1.
How would you check 45 - 23 = 22?
Q.2.
Use number pairs, or bonds, to 20 to find the incorrect calculation:
Q.3.
If 29 - 15 = 14, what could you do to check the answer?
Q.4.
How do you know that 20 - 10 = 10?
Q.5.
Which calculation could you use to check that 16 - 9 = 7 is correct?
Q.6.
If 3 + 4 + 10 + 3 = 20, what could you do to check the answer?
Q.7.
Use number pairs, or bonds, to 20 to find the incorrect calculation:
Q.8.
How could you check 62 + 38 = 100?
Q.9.
Which calculation could you use to check that 15 + 8 = 23 is correct?
Q.10.
What does 'inverse operation' mean?