Name _________________________________________ Date _____________

Part 1

All of the bridges in Part 1 are built with yellow rods for spans and red rods for supports, like the one shown here. This is a 2-span bridge like the one you just built. Note that the yellow rods are 5 cm long.

  1. Now, build a 3-span bridge.

    1. How many yellow rods did you use? _______ 

    2. How long is your bridge? _______ 

    3. How many red rods did you use? _______ 

    4. How many rods did you use altogether? _______

  1. Try to answer these questions without building a 5-span bridge. If you want, build a 5-span bridge to check your answers.

    1. How many yellow rods would you need for a 5-span bridge? _______ 

    2. How long would your bridge be? _______ 

    3. How many red rods would you need? _______ 

    4. How many rods would you need altogether? _______



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