Multiplying by a single digit whole number

To multiply 237 by 4 without using a calculator, you can set it out like this:

Diagram of a multiplication sum.Diagram of a multiplication sum.Diagram of a multiplication sum.
  1. Start with 4\times7, which is 28, so write the 8 and carry the 2 to the tens column.
  2. 4 \times 3 = 12, but remember to add the carried 2 to get 14. Write the 4 and carry the 1 to the hundreds column.
  3. 4 \times 2 = 8, and we add the carried 1 to get 9.

Therefore 237 \times 4 = 948

Multiplying with a double digit whole number

To multiply 237 by 24 without using a calculator, you can set it out like this:

Diagram of a multiplication sum.Diagram of a multiplication sum.Diagram of a multiplication sum.
  1. The first line of the calculation is the same procedure as multiplying with a single digit number.
  2. In the second line we are multiplying by 20 (two tens). As we are multiplying by tens the unit's digit will always be a zero.
  3. In a similar procedure to above:- 2 \times 7 = 14. Put the 4 in the tens column and carry the 1 to the hundreds column.
  4. 2 \times 3 = 6 - add the carried 1 to get 7 and put this in the hundreds column.
  5. 2 \times 2 = 4, nothing has been carried so put the 4 in the thousands column.
  6. Add 948 and 4740.

Therefore 237 \times 24 = 5668