Small-group support
The average base is the length of a rectangle with the same area.
Bases 8 and 4, height 5.
A trapezoid’s area uses the mean of the two bases times the height. Multiplying all three measurements counts a different solid-looking product, not the area.
Problem 1 of 4. A short entry task, a model, guided examples, then a new independent try. Frames are optional.