Multiplying Decimals by 2 Digits

Multiply decimal numbers by two digit whole numbers.

Student Tips:

• Multiply normally, ignoring decimals at first
• Count total decimal places in both numbers
• Put decimal point back with that many places from the right
• Example: 3.45 × 12 = 41.40 (multiply 345 × 12 = 4140, put decimal 2 places from right)
• Use estimation to check if your answer makes sense

Teaching Instruction: Build on 1-digit multiplication skills. Use area models or partial products method. Emphasize estimation first (3.45 × 12 is about 3 × 12 = 36). Practice decimal placement as separate step.