Area of a trapezoid

Aviation Mechanic General (AMG) practice question 11 of 25 on Mathematics. ACS element AM.I.H.K1 · difficulty: recall. Want to answer it in a timed quiz? Use the Aviation Mechanic General (AMG) practice mode.

Question bank updated 2026-09-22

QUESTIONThe area of a trapezoid is found by multiplying

AThe sum of the two bases times the height
BThe product of the two bases times one-half the height
COne-half the sum of the two bases, times the height

Show the answer and explanation

Correct answer: C. One-half the sum of the two bases, times the height

A — incorrect Leaving out the one-half factor doubles the true area; the formula requires 1/2 (base1 + base2) × height.
B — incorrect The bases are added, not multiplied, before applying the one-half and the height.
C — correct The handbook gives the trapezoid area as 1/2 (base1 + base2) × height.

BACKGROUND

A trapezoid is a four-sided figure with one pair of parallel sides, called the bases. Because the two bases differ in length, the area formula averages them: area = 1/2 (base1 + base2) × height. The height (or altitude) is the perpendicular distance between the two parallel sides. In the handbook example, bases of 14 inches and 10 inches with a height of 6 inches give 1/2 (24) × 6 = 72 square inches.

STUDY TIP

Memorize the area formulas for the rectangle, square, triangle, parallelogram, trapezoid, circle and wing; the trapezoid is the one that averages two bases.

KEY POINTS

Trapezoid: one pair of parallel sides (the bases).
Area = 1/2 (base1 + base2) × height.
Example: bases 14 in and 10 in, height 6 in, area = 72 sq in.

SOURCES

FAA-H-8083-30B ch03 "Trapezoid"

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