Multiplication Using Two Reference Numbers 89
Now subtract 8 from 37.
37 – 8 = 29
Write 29 after the equals sign.
(10 × 4) 8 × 37 = 29
–2
–3
–8
Now we multiply 29 by the main reference number, 10, to get 290.
Th en we multiply the numbers in the top two circles (2 × 3) and
add the result to 290.
(10 × 4) 8 × 37 = 290
–2
–3
- 6
–8
296 Answer
Let’s try another one:
96 × 289 =
We choose 100 and 300 as our reference numbers. We set up the
problem like this:
(100 × 3) 96 × 289 =
What do we write in the circles? Four and 11. Ninety-six is 4 below
100 and 289 is 11 below 300.
(100 × 3) 96 × 289 =
–4
–11
Now multiply the 4 below 96 by the multiplication factor, 3. Th is
gives us: 4 × 3 = 12. Draw another circle below 96 and write 12 in
this circle.