6th Grade Math Textbook, Progress

Predictions and Probability

8-16

In 2000 spins, predict the number of times the spinner above

would land on each of the following.

1. number
   5 2. number  4 3. number between 2 and 8


2. Explain how you made your predictions in exercises 1–3.

In 1000 spins, predict how many times the spinner

will land on 6.

To predict how many times, use theoretical probability.

• Find the theoretical probability of the
  spinner landing on 6.


• Multiply the probability by the
  number of trials.

Based on the probability of ^14 , you can predict the

spinner will land on 6 about 250 out of 1000 spins.

You can also use experimental probability

to make predictions.

Paul spun a 4-section spinner 40 times.

The results are shown in the table at the

right. Based on his experimental results,

how many times can Paul expect a result

of blue in the next 100 spins?

To predict how many times, use experimental probability.

• Find the experimental
  probability of spinning blue. Exp. P(blue)  


• Multiply 100 by the
  experimental probability

Paul can expect to spin blue 40 times in his next 100 spins.

2

5

16

40

number of favorable outcomes

total number of possible trials

P(6) ^14 

^14  1000 ^14 ^10100  250

favorable outcomes

possible outcomes

2 4

6 8

250

1

Color Spins

blue 16

yellow 8

red 10

orange 6

(^25)  100  (^401)  40
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