This handy Spectrum Math Grade 7 Answer Key Chapter 7 Lesson 7.4 Uniform Probability Models provides detailed answers for the workbook questions
Spectrum Math Grade 7 Chapter 7 Lesson 7.4 Uniform Probability Models Answers Key
When all outcomes of an experiment are equally likely, the event has uniform probability.
This spinner has 8 equally divided sections. Every time it is used, there is an equal chance (\(\frac{1}{8}\)) that it will land on any given number.
Chance of spinning 6 — \(\frac{1}{8}\)
Chance of spinning 3 — \(\frac{1}{8}\)
Chance of spinning 7 — \(\frac{1}{8}\)
Write yes or no to tell if each situation describes a uniform probability model.
Question 1.
a. rolling one die
Answer:
Yes,
Explanation:
By rolling one die the each of the sides numbered one through six has equal probability. so ,it describes a uniform probability.
b. rolling two dice
Answer:
No,
Explanation:
By rolling two dice it doesn’t describe as uniform probability as sum of two dice will not have uniform probability.
Question 2.
a. flipping a coin
Answer:
Yes,
Explanation:
By flipping a coin number of outcomes are equally likely so, it describe as uniform probability.
b. a spinner with 3 stars and 2 diamonds
Answer:
No,
Explanation:
A spinner with 3 stars and 2 diamonds is not uniform probability as chance of spinning is not equally likely.
Question 3.
a. calling on a girl in class
Answer:
No,
Explanation:
Generally in a class many girls may have so, calling a girl in a class is not uniform probability.
b. calling on any student in class
Answer:
Yes,
Explanation:
Generally calling any student means neither boy nor girl so, here outcomes will be likely equally and is described as a uniform probability.
Question 4.
a. winning the lottery
Answer:
No,
Explanation:
No, it doesn’t described as a uniform probability.
b. drawing an 8 from a deck of cards
Answer:
No,
Explanation:
Here it doesn’t describe as a uniform probability as no. of outcomes are equally likely.
Question 5.
calling on a boy in class
Answer:
No,
Explanation:
Here it describe a non uniform probability as no. outcomes are calculated.
b. a spinner with 5 red and 2 blue sections
Answer:
No,
Explanation:
Here it described as not in uniform probability as sections are not equally divided.
Question 6.
a. flipping a coin and rolling a die
Answer:
Yes,
Explanation:
Here flipping a coin and rolling a die are uniform probability as equally likely divided.
b. a spinner with 3 squares and 3 triangles
Answer:
Yes,
Explanation:
Here a spinner with 3 squares and 3 triangles are described as a uniform probability as no. of outcomes and events are equally likely divided.
When all outcomes of an experiment are equally likely, the event has uniform probability.
To create a uniform probability problem, divide the event into equal sections of different possibilities.
Color one section red. Color one section yellow. Color one section blue. Color one section green.
There is a \(\frac{1}{4}\) chance of spinning red, blue, yellow, or green.
This is an example of a spinner that has uniform probability.
Follow the directions to set up uniform probabilities.
Question 1.
Draw a spinner that has an equal chance of spinning a star or a diamond.
Answer:
Explanation:
Here spinner have an equal number of stars and diamonds with equal spaces.
Question 2.
Draw a spinner that has an equal chance of spinning a number 1 through 4.
Answer:
Explanation:
Here spinner has equal number of spaces with numbers 1,2,3,4.
Question 3.
Color the marbles so that there is an equal chance of pulling a blue or green marble.
Answer:
Explanation:
Here there is an equal chance of pulling blue or green marble.
Question 4.
Draw shapes in the bag so that there is an equal chance of pulling a triangle, a square, and a circle.
Answer:
Explanation:
Here from the bag there is an equal number of triangles, squares and triangles can pull with equal chance.