You have to pay £87 per week
for your rent.
You have to pay the rent for 51
weeks of the year.
How much will you pay over
the year?
• To work this out we need to:
–Multiply 87 by 51
We can do this using
‘the lattice method’
8
7
5
1
Write
Writeone
First
onenumber
number
draw adown
box
across
thethe
side
top
8
7
5
1
the box
into
rowof
and
Draw aSplit
diagonal
line
in 1
each
the boxes
1 column for each number
8
8x5=?
7
5
1
Multiply the two numbers that meet
In each box
8
4
7
5
07 x 5 = ?
1
Write the answer in the box
Put the tens in top half
the units in the bottom
8
4
7
3
0
5
8x1=?
Write the answer in the box
Put the tens in top half
the units in the bottom
5
1
8
4
7
3
0
0
5
5
1
8 7x1=?
Write the answer in the box
Put the tens in top half
the units in the bottom
8
4
7
3
0
0
5
0
8
5
1
7
Write the answer in the box
Put the tens in top half
the units in the bottom
8
4
7
3
0
0
5
0
8
5
1
7
We can ignore the numbers outside for now
Add the numbers in the diagonal columns
Remember to start at the right hand side
4
4
0
If the number
is more than
10 carry into
the next row
4
3
0
13
5
0
8
7
7
8
4
4
4
7
3
0
0
5
0
8
x
5
1
7
3
7
87 x 51 = 4437
You have to pay £87 per week
for your rent.
You have to pay the rent for 51
weeks of the year.
How much will you pay over
the year?
£4,437