Four-Rules

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Academic Skills Advice
Four Rules Refresher Sheet 2
Multiplication using Box Method:
Separate your numbers out (e.g. write 64 as 60+4) then draw a grid with each part number
as a row or column heading. Do each multiplication then add all the boxes together.
Remember the easy way for multiplying numbers with zero’s (e.g. 40x600 = 4x6 = 24 then
add the 3 0’s = 24000).
Example:

64 x 23
60 4
20 1200 80
1st fill in each square. The gray square is
20x60 so the answer is 1200.
3 180 12
Now just add all the boxes together: 1200+80+180+12 = 1472
Multiplication using Grid method:
Draw a grid for your numbers and fill in the boxes with the appropriate answers. Add the
diagonals.
Example:

64 x 23
6
2 1
1
3
1
2
8
2
1
4
8
1
8
1
8
1st fill in each square. The gray square is
2x6 so the answer 12 has been filled in.
2
0
1
1
4
0
2
Then add each diagonal from the right, the first
one is just 2. The next diagonal (shown in gray) is
8+1+8=17 so ‘7 down’, ‘carry 1’. The next is
0+2+1+1(carried)= 4, the last one is just 1)
7 2
© H Jackson 2008 / Academic Skills
1
Practice Questions:
Do the following multiplications:
2
x
x
4
6
7
5
x
6
5
3
x
5
8
© H Jackson 2008 / Academic Skills
3
4
x
4
9
5
x
3
2
6
6
x
4
4
7
x
4
3
5
6
5
7
x
7
7
x
2
3
4
8
5
4
8
5
7
2
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