4 pounds = _____ ounces
64 ounces = _____ pounds
3 kilograms = _____ grams
Conversion: Changing from one unit to another
Relationships: 1 pound = 16 ounces, 1 kilogram = 1000 grams
- Remember the conversion factors
- Multiply when going from bigger to smaller units
- Divide when going from smaller to bigger units
- Check your answer makes sense
1 pound = 16 ounces
4 pounds × 16 ounces per pound = 64 ounces
64 ounces ÷ 16 ounces per pound = 4 pounds ✓
4 pounds = 64 ounces
64 ounces = 4 pounds
3 kilograms = 3000 grams
• Conversion factor: 1 lb = 16 oz, 1 kg = 1000 g
• Multiplication: Bigger unit → smaller unit
• Division: Smaller unit → bigger unit
5 pounds or 75 ounces
4 kilograms or 3500 grams
Comparison: Making both measurements use the same unit first
Equal units: Must convert before comparing
5 pounds × 16 ounces per pound = 80 ounces
80 ounces vs 75 ounces
80 ounces > 75 ounces, so 5 pounds is heavier
5 pounds is heavier than 75 ounces
4 kilograms is heavier than 3500 grams
• Unit conversion: Always convert to same unit first
• Comparison: Only compare numbers with same units
• Conversion factor: Use known relationships
Total weight: Adding weights with the same unit
Same units: Must match before adding
Apples: 4 pounds, Oranges: 3 pounds
Both in pounds, so we can add directly
4 + 3 = 7
Lisa bought 7 pounds of fruit altogether
• Same units: Add only when units match
• Addition: Add the numbers, keep the unit
• Total: Combined amount of all items
Weight: Measure of how heavy something is
Mass: Amount of matter in an object (measured in grams/kg)
Scale: Tool used to measure weight
Unit: Standard measure for comparison
- Choose unit: Select appropriate unit for object size
- Use tool: Select proper scale for accuracy
- Read measurement: Note the number and unit
- Record: Write down with correct unit
- Convert if needed: Change to different unit when required
• U.S. Customary: pounds (lb) and ounces (oz)
• Metric System: grams (g) and kilograms (kg)
• 1 pound = 16 ounces
• 1 kilogram = 1000 grams
• 1 kg ≈ 2.2 pounds
Multi-step problem: Requires multiple operations to solve
Subtraction: Removing weight from total
7 pounds = 112 ounces (7 × 16)
112 ounces - 18 ounces = 94 ounces
94 ounces = 5 pounds and 14 ounces (94 ÷ 16 = 5 remainder 14)
The school bag now weighs 5 pounds and 14 ounces
• Unit conversion: Convert to same units before operation
• Subtraction: Remove smaller weight from larger
• Mixed units: Convert back for final answer
Estimation: Making a reasonable guess based on known values
Multiplication: Repeated addition for equal groups
12 apples × 7 ounces per apple = 84 ounces
84 ounces ÷ 16 ounces per pound = 5 pounds remainder 4 ounces
5 pounds and 4 ounces
The bag of 12 apples weighs 5 pounds and 4 ounces
• Multiplication: Equal groups × amount per group
• Division: Convert to mixed units
• Remainder: Part that doesn't make a full unit
Weight: Measure of gravitational force on an object (measured in pounds or grams)
Mass: Amount of matter in an object (measured in grams or kilograms)
Scale: Instrument used to measure weight
Unit conversion: Changing from one unit to another while keeping same value
Mixed units: Combination like pounds and ounces
- Identify units: Note what units are given and needed
- Select conversion: Choose appropriate conversion factor
- Apply operation: Multiply for larger→smaller, divide for smaller→larger
- Calculate: Perform the mathematical operation
- Check: Verify answer makes logical sense
- Express: Write answer with correct units
• 1 pound = 16 ounces
• 1 kilogram = 1000 grams
• 1 ton = 2000 pounds
• Convert to same unit before comparing or calculating
• Multiply when going from larger to smaller unit
• Divide when going from smaller to larger unit
• Always include units in your final answer
1 pound = 16 ounces
2 pounds = 32 ounces
4 pounds = 64 ounces
1 kilogram = 1000 grams
2 kilograms = 2000 grams
Learning: As weight increases, so do the corresponding units.
- Pounds to Ounces: Multiply by 16
- Ounces to Pounds: Divide by 16
- Kilograms to Grams: Multiply by 1000
- Grams to Kilograms: Divide by 1000