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Learning Math Home
Patterns, Functions, and Algebra
 
Session 3 Part A Part B Part C Part D Part E Homework
 
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Algebra Site Map
Session 3 Materials:
Notes
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Video

Session 3, Part C:
Function Machines

In This Part: About Function Machines | Running a Function Machine | Function Machines and Undoing

Take a look at this algorithm (let's call it Algorithm C):

 

Pick a number (that's the input)

 

Multiply it by 2

 

Add 3 to the answer

 

Multiply that answer by 10

 

Add 6

 

Finally, divide by 2

Draw a function machine network or print out a copy of the function machine network below to help you answer Problems C1 - C5.

non flash version of connected function machines

Problem C1

Solution  

If the input to Algorithm C is 3, what is the output?


 

Problem C2

Solution  

If the output to Algorithm C is 88, can you determine what the input was? How did you do it?


 

Problem C3

Solution  

Use the Interactive Activity to build Algorithm D, which undoes Algorithm C. How would this help with Problem C2?


 

Problem C4

Solution  

Imagine that Algorithm C and Algorithm D are connected to form one large network. What would happen to a number used as an input in this network? Think about it for a few minutes, and try a few numbers if you need to.

Connecting the two networks gets you back to your original number. Going through all these steps turns out to be a complicated way of doing nothing to a number!


Take it Further

Problem C5

Solution  

 

See if you can use the function machines network to produce the following outputs: 59, 216, 15625, 7280, 0.12345. As an additional challenge, use the fewest possible machines to do so.


 

Next > Part C (Continued): Function Machines and Undoing

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