Question

Millie makes a placemat with a triangular pattern. Each triangle has a base of 5 inches and a height of 4 inches. Millie sews together a total of 42 triangles.

Each triangle has an area of
inches2
The total area of the placemat is
inches2

Answer 1

10 inches²

420 inches²

Explanation:

1) Area of a triangular placemat:

= ½ × base × height

= ½ × 5 × 4

= 10 inches²

2) Total area of the placemat:

= Area of a placemat × Number of triangles

= 10 × 42

= 420 inches²