Session 6, Part C:
Bags, Blocks, and Balance

In This Part: Balance Scale Activity | Balance Puzzles and Equations

Here are 3 balanced scales. Use your intuition about balance to determine, for each case, how many blocks have to be in the bag.

What would happen if you removed a block from the left? What would happen if you added a block to the left?

For the purposes of the problems, the bags in each problem hold the same number of blocks, and the bags themselves weigh practically nothing.

 Video Segment In this video segment, Sue-Anne tells Professor Cossey how she solved a balance puzzle while Professor Cossey follows along on a chart. Was Sue-Anne's thinking similar to or different from, your own strategy for these problems? Watch the video segment after you have completed the Bags and Blocks interactive activity and compare your strategy with Sue-Anne's. If you get stuck during the activity, you can watch the video segment to help you. Will Sue-Anne's strategy work for any balance puzzle? Will yours? Explain. You can find this segment on the session video, approximately 13 minutes and 31 seconds after the Annenberg Media logo.

 Session 6: Index | Notes | Solutions | Video