A trapezoid is divided into seven strips of equal width as shown. What fraction of the trapezoid's area is shaded? Explain why your answer is correct.

![](https://cdn.mathpix.com/cropped/2024_04_17_eef89f05a2bdd3817ad8g-1.jpg?height=301&width=613&top_left_y=787&top_left_x=707)
We can fit the trapezoid together with a rotated copy of itself to make a parallelogram:

![](https://cdn.mathpix.com/cropped/2024_04_17_eef89f05a2bdd3817ad8g-1.jpg?height=309&width=1000&top_left_y=1198&top_left_x=514)

The stripes on the two trapezoids join to make seven stripes across the parallelogram. These stripes are congruent to each other, so the shaded ones cover exactly $\frac{4}{7}$ of the area of the parallelogram. Since the two copies of the original trapezoid are identical, the stripes must also cover $\frac{4}{7}$ of the area of each trapezoid.