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Middle School Math • Grade 6

Area of a Trapezoid Worksheet: Grade 6

Focus: Decimal dimensions, vertical trapezoids, and multi-step area calculations.

Question 1: Decimal Dimensions
[1 Point]

Calculate the area of a trapezoid with parallel sides b₁ = 4.5 cm and b₂ = 7.5 cm, and perpendicular height h = 3.6 cm.

Show Answer & Steps
b₁ + b₂ = 4.5 + 7.5 = 12.0 cm
Area = 0.5 × 12.0 × 3.6 = 6.0 × 3.6 = 21.6 cm²
Question 2: Vertical / Rotated Trapezoid
[1 Point]

A trapezoid is standing vertically. Its two vertical parallel sides measure 12 m and 18 m. The horizontal distance between these two vertical walls is 8.5 m. What is the enclosed cross-sectional area?

Show Answer & Steps
Note: The horizontal distance is the height h = 8.5 m.
Sum of parallel vertical bases = 12 + 18 = 30 m
Area = ½ × 30 × 8.5 = 15 × 8.5 = 127.5 m²
Question 3: Distractor Side Lengths
[1 Point]

A student measures all 4 sides of a desk mat: Top = 14 cm, Bottom = 22 cm, Left leg = 8 cm, Right leg = 9 cm. A ruler shows the perpendicular vertical height is 7.2 cm. Calculate the area.

Show Answer & Steps
Discard slant side legs (8 cm and 9 cm).
Sum of bases = 14 + 22 = 36 cm
Area = ½ × 36 × 7.2 = 18 × 7.2 = 129.6 cm²
Question 4: Composite Shape (House Gable)
[1 Point]

An architectural window consists of a bottom rectangle of width 8 ft and height 5 ft, topped with an inverted trapezoid having top width 12 ft, bottom width 8 ft, and height 3 ft. Find the total area of the window.

Show Answer & Steps
Area of rectangle = 8 × 5 = 40 ft²
Area of trapezoid = ½ × (8 + 12) × 3 = ½ × 20 × 3 = 30 ft²
Total Area = 40 + 30 = 70 ft²
Question 5: Real-World Word Problem
[1 Point]

A backyard patio is shaped like a trapezoid with bases 15 feet and 21 feet. The distance between the parallel edges is 11 feet. If flagstone paving costs $4.50 per square foot, what is the total cost to pave the patio?

Show Answer & Steps
Patio Area = ½ × (15 + 21) × 11 = ½ × 36 × 11 = 18 × 11 = 198 ft²
Total Cost = 198 × $4.50 = $891.00
Question 6: Fractional Dimensions
[1 Point]

Find the area of a trapezoid whose base 1 is 2 ½ yards, base 2 is 3 ½ yards, and height is 1 ¼ yards.

Show Answer & Steps
b₁ = 2.5, b₂ = 3.5, h = 1.25
Sum of bases = 2.5 + 3.5 = 6.0 yd
Area = ½ × 6.0 × 1.25 = 3 × 1.25 = 3.75 yd² (or 3 ¾ yd²)