SME
Grade 3 Math · Problem type
Multiply to find a total mass
Use this for “5 bags of 3 kg each. How heavy in all?”
Diagram
5 bags of 3 kg = 15 kg
This is an example. Type your own values to start a new problem.
Bags
×
Mass of each bag (kg)
=
Total mass (kg)
Formulas
5 × 3 = 15
Bags × mass of each bag = total mass
Assumptions
•
Every bag has the same mass.
•
Bags × mass of each bag = total mass.
•
To share a mass equally, divide.
Step-by-step
WE KNOW
Bags: 5
Mass of each bag: 3 kg
FIND
total mass
Step 1 · Find total mass
5 × 3 = ?
Bags × mass of each bag = total mass
Multiply the bags by the mass of each bag.
10 × 3 = 30. Five groups are half of that: 15
Total mass = 15 kg
Check
Put the numbers back in. Both sides should match.
5 × 3 = 15 ✓
Topic check
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