# Experimental Probability Worksheets

Experimental Probability Worksheets
• Page 1
1.
A pair of dice is cast 20 times, and on 2 of these occasions, the sum of the numbers facing up is 5. What is the experimental probability of the outcome 5?
 a. 1 b. 0.1 c. 0.01 d. 10

#### Solution:

P(event) = Number of times an event happensNumber of trials made

P(outcome 5) = number of times sum 5 occuredtotal number of times dice thrown

= 220 = 110
[Simplify.]

The experimental probability of the outcome 5 is 110. .

2.
In a blub factory, 1000 bulbs were checked. Out of which 50 were found to be defective. What is the experimental probability a blub is defective?
 a. 6% b. 5% c. 15% d. 2%

#### Solution:

P(event) = Number of times an event happensNumber of trials made

P(defective bulb) = number of times "defective blub" occurstotal number of bulbs checked = 501000 = 5%.
[Simplify.]

The probability of a defective bulb is 5%.

3.
Annie planted 85 seeds out of which 17 were lemon seeds. Find the experimental probability of not choosing a lemon seed.
 a. $\frac{1}{85}$ b. $\frac{1}{9}$ c. $\frac{1}{5}$ d. $\frac{4}{5}$

#### Solution:

P(lemon seed) = Number of lemon seeds plantedTotal number of seeds planted

= 17 / 85 = 1 / 5
[Substitute and simplify.]

P(no lemon seed) = 1 - P(lemon seed)

= 1 - 1 / 5 = 4 / 5
[Substitute and simplify.]

Experimental probability of not choosing a lemon seed is 4 / 5.

4.
The table shows the data of the books sold by a bookstore on different subjects during the first week of June. Find the probability of selling a math book.

 a. 8 out of 43 b. 25 out of 129 c. 44 out of 129 d. 12 out of 129

#### Solution:

Total number of books sold during the week = 44 + 36 + 24 + 25 = 129
[Add the number of books in each subject.]

Number of math books sold = 44

P(math book) = Number of math books sold Total number of books sold = 44 / 129
[Substitute the values.]

The probability of selling a math book is 44 out of 129 .

5.
Find the probability of getting an odd number, when a number cube is rolled.
 a. 0.6 b. 0.5 c. 0.4 d. 0.71

#### Solution:

Number of favorable outcomes = number of odd numbers = 3.

Total number of possible outcomes = numbers on the cube = 6

Probability (getting an odd number) = Number of favorable outcomesTotal number of possible outcomes

= 36
[Simplify.]

= 12
[Convert fraction to decimal.]

= 0.5.
[Convert fraction to decimal.]

6.
Mary rolls a number cube. What is the probability of getting an even number?
 a. 0.5 b. 1 c. 1.5 d. 0.75

#### Solution:

Probability of getting an even number = Number of favorable eventsTotal number of events

Total number of events on rolling a number cube = { 1,2,3,4,5,6 } = 6.

Number of favorable events of getting an even number = { 2,4,6 } = 3.

Probability of getting an even number = 36
[Simplify.]

= 12
[Convert fraction to decimal.]

= 0.5

7.
There are 4 blackberries and 5 apples in a bag. If Tom picks a fruit at random from the bag, then what is the probability of the fruit being a blackberry?
 a. 0.25 b. 0.32 c. 0.49 d. 0.44

#### Solution:

Number of favorable outcomes = number of blackberries = 4.

Total number of possible outcomes = number of fruits = 9

Probability (getting a blackberry) = Number of favorable outcomes Total number of possible outcomes.

= 49
[Convert fraction to decimal.]

= 0.44

8.
Use a decimal to express the probability that L is selected from the word UMBRELLA.
 a. 0.75 b. 0.25 c. 0.5 d. 0.65

#### Solution:

Number of favorable outcomes = number of 'L' = 2.

Total number of possible outcomes = number of alphabets = 8

Probability (getting L) = Number of favorable outcomes Total number of possible outcomes

= 28
[Simplify.]

= 14
[Convert fraction to decimal.]

= 0.25

9.
What is the probability of getting a number, which is a multiple of 4 when the spinner is turned?

 a. 0.75 b. 0.5 c. 0.35 d. 0.25

#### Solution:

Number of favorable outcomes = Multiples of 4 = 2.

Total number of possible outcomes = Numbers on spinner = 8

Probability (getting a multiple of 4) = Number of favorable outcomes  Total number of possible outcomes

= 28
[Simplify.]

= 14
[Convert fraction to decimal.]

= 0.25

10.
What are the odds in favor of spinning yellow in the figure?

 a. 1 : 4 b. 1 : 2 c. 3 : 4 d. 1 : 1

#### Solution:

The odds in favor of an event = Number of favorable outcomes / Number of unfavorable outcomes

Number of favorable outcomes = 4
[Since there are 4 yellow colored sections in the spinner.]

Number of unfavorable outcomes = 8
[Since there are 8 sections colored other than yellow in the spinner.]

Odds in favor of spinning yellow = 4 / 8 = 1 : 2
[Substitute and simplify.]

So, the odds in favor of spinning yellow is 1 : 2.