Multiplication

Multiplying a three digit number by a one digit number

How to multiply a three digit number by a one digit number (for example 159 * 7).

• Place one number above the other so that the ones place digits are lined up. Draw a line under the bottom number.

159
  7

• Multiply the two ones place digits. (9 * 7 = 63). This number is larger than 10, so place the six above the tens place column and place the three below the line in the ones place column.

 6
159
  7
  3

• Multiply the digit in the tens place column (5) by the digit in the ones place of the second number (7). The result is 5 * 7 = 35. Add the 6 to the 35 (35 + 6 = 41). Place the one below the line and to the left of the other number. Place the 4 above the hundreds column. below the line.

 46
 159
   7
  13

• Multiply the digit in the hundreds place column (1) by the digit in the ones place of the second number (7). The result is 1 * 7 = 7. Add the 4 to the 7 (4 + 7 = 11). Place this below the line and to the left of the other number.

 46
 159
   7
1113