Group Activity Cards
Use groups of 2.
Materials: Centimeter grid paper, metric ruler, scissors
| Strange Arranging
Cut out an 8 × 8 grid from centimeter grid paper. What is the area of the square?
Draw lines to make triangles A and B and trapezoids C and D, as shown in Figure A below. Find the area of each figure in square centimeters. (The sum of these areas should equal the area you found above.)
Cut out the triangles and trapezoids and arrange them as shown in Figure B below. The area of Figure B is 65 square centimeters. Is this the area you found for Figure A? If not, how do you explain the difference? Discuss your results with other pairs.