Math Unit 8 and Lesson 11 Probability Unit Test

Question 5
A spinner has 8 equally sized sections labeled as A, B, C, D, E, F, G, H.
Part 1: How many contestants and vowels are listed on the spinner?
Part 2: What is the theoretical probability the spinner will land on a consonant?
____ Enter the probability as a simplified fraction.
Part 3: If the spinner is used 160 times, how many times should the spinner land on a consonant?
The spinner is expected to land on a consonant _____ times.

1 answer

To solve the problems related to the spinner, let's break it down into parts.

Part 1: Contestants and Vowels

The spinner has the sections labeled A, B, C, D, E, F, G, H.

  • Vowels: A, E (there are 2 vowels)
  • Consonants: B, C, D, F, G, H (there are 6 consonants)

So, the spinner has:

  • Number of contestants (sections): 8
  • Number of vowels: 2

Part 2: Theoretical Probability of Landing on a Consonant

To find the probability of landing on a consonant:

  • Total sections = 8
  • Number of consonants = 6

The probability \( P \) of landing on a consonant is calculated as: \[ P(\text{consonant}) = \frac{\text{Number of consonants}}{\text{Total sections}} = \frac{6}{8} = \frac{3}{4} \]

Part 3: Expected Number of Times Landing on a Consonant

If the spinner is used 160 times, the expected number of times it will land on a consonant can be calculated by multiplying the total spins by the probability of landing on a consonant.

So: \[ \text{Expected number of times} = 160 \times P(\text{consonant}) = 160 \times \frac{3}{4} = 160 \times 0.75 = 120 \]

Summary of Answers

  • Part 1: 8 contestants and 2 vowels.
  • Part 2: The theoretical probability the spinner will land on a consonant is \( \frac{3}{4} \).
  • Part 3: The spinner is expected to land on a consonant 120 times.