Multiplying by 429

To multiply a multiple of 7 by 429, perform the following:

• Divide the number by 7.

• Multiply the number by 3.

• Write the result on the right, using three digits. Then write the result on the left.

Example:

14 × 429 =

Solution:

• 14 ÷ 7 = 2

• 2 × 3 = 6

• Write 006 as 6 is the result and you must use three-digits. Then write the 6 on the left. The final answer is 6006.

Answer:

14 × 429 = 6006.

Example:

84 × 429 =

Solution:

• 84 ÷ 7 = 12

• 12 × 3 = 36

• Write 036 on the right (using three digits). Then write 36 on the left. The final answer is 36036.

84 × 429 = 36036.

Note: This trick works because .