A pair of kids and a pair of adults decided to compete in a three-legged race. The kids got to start 21 meters ahead of the adults, since they had shorter legs. When they were told to start, the kids hobbled forward at a rate of 1 meter per second, and the adults hobbled after them at a rate of 4 meters per second. Soon they were side-by-side. How long did that take? How far did the adults go?

Koda is making birdhouses for a park. the instructions tell him how many of each wooden shape is needed for one birdhouse. complete each statement to adjust the number of shapes for each new situation if he follows the given instructions. to make 8 birdhouses, koda will trapezoids.  for koda to make birdhouses, he will need 12 rectangles. if koda uses 4 squares to make birdhouses, he will use triangles.