 Double 47 is 94.

# Addition and Subtraction (Year 4)

In year Four, the second year in KS2, children will be exposed to more difficult addition and subtraction problems in Maths, such as four figure numbers or negatives. They will however be taught the best methods to use to work out the answers to these problems.

Addition and subtraction is adding numbers together or taking them away from each other. Knowing how to work out addition and subtraction problems comes in very handy when dealing with money in everyday life. Imagine that you have £10 and wish to buy two items that cost £3.47 and £6.91... do you have enough money? Well, £3.47 + £6.91 = £10.38 so you'd be 38p short! See how important it is to be able to add and subtract?

Test your knowledge of addition and subtraction by playing the following Year Four quiz.

1.
Which strategy would be best to calculate 827 + 6?
Add 20 to 827 then subtract 14
Count 827 on from 6
Subtract 10 from 827 then add 4
Most maths problems can be made simpler
2.
What would we add to 56 to total 100?
44
45
54
64
100 - 56 = 44
3.
What is the best method of subtracting 21?
Subtract 20 subtract 1
e.g. 56 - 21 so:
56 - 20 = 36
then 36 - 1 = 35
4.
Which is a good strategy for adding 19?
Add 20 and take away 11
Add 20 and take away 1
e.g. 46 + 19 so:
46 + 20 = 66
then 66 - 1 = 65
5.
Which number sentence is incorrect?
28 + 35 = 63
63 - 35 = 28
35 + 28 = 63
28 - 35 = 63
The other correct number sentence would be 63 - 28 = 35
6.
What is the sum of 37 + 28?
9
63
65
75
Add the 10s first and then the units
30 + 20 = 50
then 7 + 8 = 15
then 50 + 15
7.
What is the missing number in 350 + ___ = 1,000?
450
550
650
750
100 - 35 = 65
so 1,000 - 350 = 650
8.
What is double 47?
84
87
92
94
40 x 2 = 80 and 7 x 2 = 14
80 + 14 = 94
9.
Which is the best strategy to calculate 38 + 37?
Count on 37 from 38
Double 38 and subtract 1
Add 50 to 38 then subtract 13
Multiply 38 by 3 subtract 39
2 x 8 = 16 and 2 x 30 = 60
60 + 16 = 76
76 - 1 = 75
10.
If we subtract a large number from a small number the total will be?
A fraction
A decimal
A multiple
A negative number
e.g. 8 - 10 = -2

Author:  Amanda Swift