📚 Topic Summary
Multiplying decimals by whole numbers is similar to multiplying whole numbers, but you need to remember to place the decimal point correctly in the answer. First, multiply the numbers as if the decimal point wasn't there. Then, count the number of decimal places in the decimal number. Finally, place the decimal point in the answer so that it has the same number of decimal places. For instance, to solve $3.25 \times 4$, you'd multiply $325 \times 4 = 1300$. Since 3.25 has two decimal places, the final answer is 13.00 or 13.
Let's say you want to buy 5 candy bars, and each candy bar costs $1.25. How much money do you need? This problem is easily solved using decimal multiplication!
🧠 Part A: Vocabulary
Match the term with its correct definition:
| Term |
Definition |
| 1. Decimal |
a. The answer to a multiplication problem. |
| 2. Whole Number |
b. A number without a fraction or decimal. |
| 3. Product |
c. A number that uses a decimal point to show part of a whole. |
| 4. Place Value |
d. Multiplying a number by itself. |
| 5. Exponent |
e. The value of a digit based on its position in a number. |
📝 Part B: Fill in the Blanks
Complete the paragraph using the words: decimal, multiply, whole number, product, places.
When we ______ a ______ by a ______, we first ignore the ______. We then count the number of decimal ______ in the original decimal and put that many ______ in our final ______.
💡 Part C: Critical Thinking
Sarah wants to buy 3 notebooks that cost $2.75 each and 2 pens that cost $1.50 each. Explain how she can use multiplication to find the total cost of her purchase.