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Activity 10

Probability

Give Me 5!

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order of operations

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mental math

 

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basic computation

Students investigate the results of tossing 5 coins.

 

Materials

They compare what happens to what is expected to

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student activity sheets (provided)

happen.

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TI-73 ³

 

Setup

♦If your TI-73s have not been used for any random numbers prior to this activity, you and your students need to store an integer “seed value” to rand in each TI-73.

With each rand execution, the TI-73 generates the same random-number sequence for a given seed value. The TI-73 factory-set seed value for rand is 0. To generate a different random-number sequence, store any non-zero seed value to rand.

1.Enter the number you want for your seed value. Have students use different seed values. (In the example at the right, 1 is used.)

2.Now press X 1 " " 1 b 1 " " 1 b b.

(For more information about seed values, refer to the “1 Probability Menu” section in the Math chapter of the TI-73 Guidebook ￿.)

♦Discuss with students events that are equally likely to occur, such as tossing a coin and getting a head or a tail.

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If you do not enter a seed value, rand uses whatever value happens to be the current seed. If there is no seed, it uses the factory- set value of 0.

If you want to restore the factory-set seed value, store 0 to rand or reset the defaults.

© 1998 TEXAS INSTRUMENTS INCORPORATED