Perimeter = 2 × (length + width)
P = 2 × (12 + 8) = 2 × 20 = 40 feet
Cost = Perimeter × Price per foot
Cost = 40 × $3 = $120
Rectangle B length = 3 × 10 = 30 cm
Rectangle B width = 6 cm (same as A)
P_A = 2 × (10 + 6) = 2 × 16 = 32 cm
P_B = 2 × (30 + 6) = 2 × 36 = 72 cm
Difference = P_B - P_A = 72 - 32 = 40 cm
Area = side × side
A = 15 × 15 = 225 m²
Grass cost = Area × Cost per square meter
Grass cost = 225 × $2 = $450
Perimeter = 4 × side
P = 4 × 15 = 60 m
Fencing cost = Perimeter × Cost per meter
Fencing cost = 60 × $4 = $240
Total cost = Grass cost + Fencing cost
Total cost = $450 + $240 = $690
Multiple-step problems: Require more than one calculation to solve.
Break the problem into smaller, manageable steps.
- Find the perimeter of the garden
- Multiply perimeter by cost per foot
- Calculate total cost
Each step builds on the previous one. Solve one step at a time.
Break complex problems into simpler sub-problems.
Organizing information: Helps track what you know and what you need.
List known information and what needs to be found.
Known: Rectangle A (10cm × 6cm), Rectangle B (width=6cm, length=3×10cm)
Find: Difference in perimeters
Steps: Calculate each perimeter, then find difference
Write down all given information before starting calculations.
Organize information to avoid missing steps.
Checking work: Ensures accuracy in multiple-step problems.
Verify each step before proceeding to the next.
Step 1: Area = 15 × 15 = 225 m² ✓
Step 2: Grass cost = 225 × $2 = $450 ✓
Step 3: Perimeter = 4 × 15 = 60 m ✓
Step 4: Fencing cost = 60 × $4 = $240 ✓
Step 5: Total = $450 + $240 = $690 ✓
One error in an early step affects all subsequent steps.
Check each calculation before moving to the next step.
Definition: Problems requiring more than one calculation to solve
Characteristics: Two or more operations needed
Approach: Break into smaller, sequential steps
Step 1: Read the problem carefully
Step 2: Identify what is being asked
Step 3: Determine the steps needed
Definition: Comparing quantities using multiplication
Keywords: "times larger", "multiplied by", "groups of"
Operation: Usually involves multiplication or division
Perimeter: Distance around a shape (linear units)
Area: Space inside a shape (square units)
Units: Always include correct measurement units
- Read carefully: Understand what the problem is asking
- Identify information: List what is given and what is needed
- Plan steps: Determine the sequence of calculations needed
- Solve step-by-step: Complete one calculation at a time
- Check work: Verify each step before proceeding
- State answer: Include proper units and context
- Write given information: List all known values
- Identify unknown: What do you need to find?
- Plan calculations: Write out the steps in order
- Show work: Write each step clearly
- Label answers: Include units for each calculation