Multiply whole numbers: word problems
key notes:
Read the Problem Carefully:
- Identify and underline the numbers and keywords.
- Determine what is being asked and the operation needed.
Identify Keywords:
- Words like “total,” “each,” “per,” and “in all” often indicate multiplication.
Break Down the Problem:
- Convert the word problem into a mathematical expression or equation.
- Identify the multiplicand (number to be multiplied) and the multiplier (number by which to multiply).
Set Up the Multiplication:
- Write down the numbers to be multiplied.
- Choose the appropriate multiplication method (e.g., column method, grid method).
Solve the Problem:
- Perform the multiplication.
- Double-check calculations for accuracy.
Write the Answer:
- Ensure the answer is in the context of the problem.
- Include units (e.g., dollars, items, etc.) if applicable.
Check the Reasonableness:
- Estimate the result to ensure it makes sense with the problem’s context.
- Reevaluate if the answer seems unreasonable or incorrect.
Example Problem:
Problem: A school is organizing a field trip for 8 classes. Each class has 25 students. How many students are going on the field trip in total?
Solution Steps:
- Read the Problem: Identify the number of classes and students per class.
- Keywords: “total” and “each” indicate multiplication.
- Break Down:
- Multiplicand: 25 (students per class)
- Multiplier: 8 (number of classes)
- Set Up the Multiplication: 25 × 8
- Solve:
- (25 times 8 = 200)
- Write the Answer: There are 200 students going on the field trip.
- Check Reasonableness: Estimate: 20 × 8 = 160; 200 is a reasonable result.
Learn with an example
🗼 Carson made 6 pans of brownies. He cut each pan into 38 brownies.
How many brownies did Carson end up with?
______ brownies
There were 6 pans, each of which was cut into 38 brownies. Multiply:
Carson ended up with 228 brownies.
🗼 A soda company makes 4 kinds of soda. A grocery store chain ordered 9,241 bottles of each kind of soda.
How many bottles of soda in total did the grocery store chain order?
_____ bottles of soda
There are 4 kinds of soda, and the store ordered 9,241 bottles of each. Multiply:
The grocery store chain ordered 36,964 bottles of soda.
🗼 A carpet store has 6 commercials every hour on a local television station.
How many commercials will the store have in 82 hours?
_______ commercials
There are 82 hours, each of which has 6 commercials. Multiply:
The store shows 492 commercials in 82 hours.
Let’s practice!🖊️