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Amy Ferguson Moncure

7th Grade Math ยท Unit 7

Experimental
Probability

Experimental probability is the number of successes over the number of trials.

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Key Ideas Easy Medium Hard
What to Remember

Successes over trials

Experimental probability is successes over trials.

More trials

More trials tend to move the experimental probability toward the theoretical probability.

A bigger sample is not closer on every single try.

Level 1

Easy

A short experiment

Example
An experiment recorded 1 successes in 2 trials for a coin landing on heads. Find the experimental probability.

experimental probability = times it happenednumber of trials

experimental probability = 12

Answer: 12

1
An experiment recorded 2 successes in 5 trials for a spinner landing on red. Find the experimental probability.
Show Answer

experimental probability = times it happenednumber of trials

experimental probability = 25

Answer: 25

2
An experiment recorded 3 successes in 4 trials for a die showing an odd number. Find the experimental probability.
Show Answer

experimental probability = times it happenednumber of trials

experimental probability = 34

Answer: 34

3
An experiment recorded 1 successes in 6 trials for rolling a 5. Find the experimental probability.
Show Answer

experimental probability = times it happenednumber of trials

experimental probability = 16

Answer: 16

4
An experiment recorded 5 successes in 6 trials for rolling a number less than 6. Find the experimental probability.
Show Answer

experimental probability = times it happenednumber of trials

experimental probability = 56

Answer: 56

5
An experiment recorded 4 successes in 6 trials for drawing a blue marble. Find the experimental probability.
Show Answer

experimental probability = times it happenednumber of trials

experimental probability = 46

23

Answer: 23

6
An experiment recorded 2 successes in 8 trials for picking a green card. Find the experimental probability.
Show Answer

experimental probability = times it happenednumber of trials

experimental probability = 28

14

Answer: 14

7
An experiment recorded 3 successes in 5 trials for making a basket. Find the experimental probability.
Show Answer

experimental probability = times it happenednumber of trials

experimental probability = 35

Answer: 35

8
An experiment recorded 7 successes in 8 trials for a spinner landing on a number greater than 1. Find the experimental probability.
Show Answer

experimental probability = times it happenednumber of trials

experimental probability = 78

Answer: 78

9
An experiment recorded 3 successes in 10 trials for selecting a winning ticket. Find the experimental probability.
Show Answer

experimental probability = times it happenednumber of trials

experimental probability = 310

Answer: 310

10
An experiment recorded 6 successes in 8 trials for flipping heads in a short run. Find the experimental probability.
Show Answer

experimental probability = times it happenednumber of trials

experimental probability = 68

34

Answer: 34

Level 2

Medium

Simplify the result

Example
An experiment recorded 4 successes in 10 trials for a coin landing on heads in a class experiment. Find the experimental probability.

experimental probability = times it happenednumber of trials

experimental probability = 410

25

Answer: 25

1
An experiment recorded 6 successes in 8 trials for rolling an even number. Find the experimental probability.
Show Answer

experimental probability = times it happenednumber of trials

experimental probability = 68

34

Answer: 34

2
An experiment recorded 2 successes in 6 trials for spinning blue. Find the experimental probability.
Show Answer

experimental probability = times it happenednumber of trials

experimental probability = 26

13

Answer: 13

3
An experiment recorded 8 successes in 12 trials for drawing a red marble. Find the experimental probability.
Show Answer

experimental probability = times it happenednumber of trials

experimental probability = 812

23

Answer: 23

4
An experiment recorded 6 successes in 9 trials for picking a ripe apple. Find the experimental probability.
Show Answer

experimental probability = times it happenednumber of trials

experimental probability = 69

23

Answer: 23

5
An experiment recorded 4 successes in 12 trials for landing on green. Find the experimental probability.
Show Answer

experimental probability = times it happenednumber of trials

experimental probability = 412

13

Answer: 13

6
An experiment recorded 10 successes in 15 trials for selecting a mystery book. Find the experimental probability.
Show Answer

experimental probability = times it happenednumber of trials

experimental probability = 1015

23

Answer: 23

7
An experiment recorded 6 successes in 10 trials for a free throw going in. Find the experimental probability.
Show Answer

experimental probability = times it happenednumber of trials

experimental probability = 610

35

Answer: 35

8
An experiment recorded 9 successes in 12 trials for a spinner landing on purple. Find the experimental probability.
Show Answer

experimental probability = times it happenednumber of trials

experimental probability = 912

34

Answer: 34

9
An experiment recorded 8 successes in 10 trials for drawing a heart. Find the experimental probability.
Show Answer

experimental probability = times it happenednumber of trials

experimental probability = 810

45

Answer: 45

10
An experiment recorded 12 successes in 16 trials for pulling a striped sock. Find the experimental probability.
Show Answer

experimental probability = times it happenednumber of trials

experimental probability = 1216

34

Answer: 34

Level 3

Hard

Which experiment is closer

Example
The theoretical probability of heads is 1 out of 2. One experiment had 3 successes in 10 trials. A larger experiment had 48 successes in 100 trials. Which experiment is closer to the theoretical probability?

theoretical probability = 12

small experiment = 310

distance = 15

larger experiment = 48100

distance = 150

The larger experiment is closer this time.

More trials tend to move the experimental probability toward the theoretical probability. A bigger sample is not closer on every single try.

Answer: the experiment with 100 trials

1
The theoretical probability of tails is 1 out of 2. One experiment had 2 successes in 8 trials. A larger experiment had 45 successes in 100 trials. Which experiment is closer to the theoretical probability?
Show Answer

theoretical probability = 12

small experiment = 28

distance = 14

larger experiment = 45100

distance = 120

The larger experiment is closer this time.

More trials tend to move the experimental probability toward the theoretical probability. A bigger sample is not closer on every single try.

Answer: the experiment with 100 trials

2
The theoretical probability of rolling a 6 is 1 out of 6. One experiment had 1 successes in 12 trials. A larger experiment had 15 successes in 90 trials. Which experiment is closer to the theoretical probability?
Show Answer

theoretical probability = 16

small experiment = 112

distance = 112

larger experiment = 1590

distance = 0

The larger experiment is closer this time.

More trials tend to move the experimental probability toward the theoretical probability. A bigger sample is not closer on every single try.

Answer: the experiment with 90 trials

3
The theoretical probability of rolling an even number is 1 out of 2. One experiment had 7 successes in 20 trials. A larger experiment had 52 successes in 100 trials. Which experiment is closer to the theoretical probability?
Show Answer

theoretical probability = 12

small experiment = 720

distance = 320

larger experiment = 52100

distance = 150

The larger experiment is closer this time.

More trials tend to move the experimental probability toward the theoretical probability. A bigger sample is not closer on every single try.

Answer: the experiment with 100 trials

4
The theoretical probability of drawing a red marble is 1 out of 4. One experiment had 1 successes in 8 trials. A larger experiment had 22 successes in 80 trials. Which experiment is closer to the theoretical probability?
Show Answer

theoretical probability = 14

small experiment = 18

distance = 18

larger experiment = 2280

distance = 140

The larger experiment is closer this time.

More trials tend to move the experimental probability toward the theoretical probability. A bigger sample is not closer on every single try.

Answer: the experiment with 80 trials

5
The theoretical probability of spinning blue is 1 out of 5. One experiment had 1 successes in 10 trials. A larger experiment had 18 successes in 100 trials. Which experiment is closer to the theoretical probability?
Show Answer

theoretical probability = 15

small experiment = 110

distance = 110

larger experiment = 18100

distance = 150

The larger experiment is closer this time.

More trials tend to move the experimental probability toward the theoretical probability. A bigger sample is not closer on every single try.

Answer: the experiment with 100 trials

6
The theoretical probability of drawing a green card is 2 out of 5. One experiment had 2 successes in 10 trials. A larger experiment had 36 successes in 100 trials. Which experiment is closer to the theoretical probability?
Show Answer

theoretical probability = 25

small experiment = 210

distance = 15

larger experiment = 36100

distance = 125

The larger experiment is closer this time.

More trials tend to move the experimental probability toward the theoretical probability. A bigger sample is not closer on every single try.

Answer: the experiment with 100 trials

7
The theoretical probability of picking a winning ticket is 1 out of 10. One experiment had 0 successes in 10 trials. A larger experiment had 8 successes in 100 trials. Which experiment is closer to the theoretical probability?
Show Answer

theoretical probability = 110

small experiment = 010

distance = 110

larger experiment = 8100

distance = 150

The larger experiment is closer this time.

More trials tend to move the experimental probability toward the theoretical probability. A bigger sample is not closer on every single try.

Answer: the experiment with 100 trials

8
The theoretical probability of drawing a heart is 1 out of 4. One experiment had 4 successes in 10 trials. A larger experiment had 26 successes in 100 trials. Which experiment is closer to the theoretical probability?
Show Answer

theoretical probability = 14

small experiment = 410

distance = 320

larger experiment = 26100

distance = 1100

The larger experiment is closer this time.

More trials tend to move the experimental probability toward the theoretical probability. A bigger sample is not closer on every single try.

Answer: the experiment with 100 trials

9
The theoretical probability of rolling a prime is 3 out of 6. One experiment had 8 successes in 20 trials. A larger experiment had 47 successes in 100 trials. Which experiment is closer to the theoretical probability?
Show Answer

theoretical probability = 36

small experiment = 820

distance = 110

larger experiment = 47100

distance = 3100

The larger experiment is closer this time.

More trials tend to move the experimental probability toward the theoretical probability. A bigger sample is not closer on every single try.

Answer: the experiment with 100 trials

10
The theoretical probability of landing on a shaded section is 3 out of 8. One experiment had 2 successes in 8 trials. A larger experiment had 35 successes in 100 trials. Which experiment is closer to the theoretical probability?
Show Answer

theoretical probability = 38

small experiment = 28

distance = 18

larger experiment = 35100

distance = 140

The larger experiment is closer this time.

More trials tend to move the experimental probability toward the theoretical probability. A bigger sample is not closer on every single try.

Answer: the experiment with 100 trials

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