Table of contents
- 1. Intro to Stats and Collecting Data55m
- 2. Describing Data with Tables and Graphs1h 55m
- 3. Describing Data Numerically1h 45m
- 4. Probability2h 16m
- 5. Binomial Distribution & Discrete Random Variables2h 33m
- 6. Normal Distribution and Continuous Random Variables1h 38m
- 7. Sampling Distributions & Confidence Intervals: Mean1h 3m
- 8. Sampling Distributions & Confidence Intervals: Proportion1h 12m
- 9. Hypothesis Testing for One Sample1h 1m
- 10. Hypothesis Testing for Two Samples2h 8m
- 11. Correlation48m
- 12. Regression1h 4m
- 13. Chi-Square Tests & Goodness of Fit1h 20m
- 14. ANOVA1h 0m
4. Probability
Basic Concepts of Probability
Problem 3.1.2a
Textbook Question
2. Determine whether each number could represent the probability of an event. Explain your reasoning. a. 25/25

1
Step 1: Recall the definition of probability. Probability is a measure of the likelihood of an event occurring, and it is always a value between 0 and 1, inclusive. This means probabilities cannot be negative or greater than 1.
Step 2: Simplify the given fraction, 25/25. Perform the division to determine its value. Mathematically, dividing any number by itself results in 1.
Step 3: Compare the simplified value (1) to the range of valid probabilities (0 ≤ P ≤ 1). Since 1 is within this range, it is a valid probability.
Step 4: Explain the reasoning. A probability of 1 indicates that the event is certain to occur. For example, if you have 25 favorable outcomes out of 25 possible outcomes, the event is guaranteed to happen.
Step 5: Conclude that the number 25/25 could represent the probability of an event because it simplifies to 1, which is within the valid range for probabilities.

This video solution was recommended by our tutors as helpful for the problem above
Video duration:
1mPlay a video:
Was this helpful?
Key Concepts
Here are the essential concepts you must grasp in order to answer the question correctly.
Probability Range
Probability is a measure of the likelihood of an event occurring, and it is always expressed as a number between 0 and 1. A probability of 0 indicates that an event will not occur, while a probability of 1 indicates certainty that the event will occur. Any value outside this range is not valid for representing probabilities.
Recommended video:
Introduction to Probability
Fraction Representation
Fractions can be used to express probabilities, where the numerator represents the number of favorable outcomes and the denominator represents the total number of possible outcomes. In the case of 25/25, this fraction simplifies to 1, which is a valid probability indicating certainty that the event will occur.
Recommended video:
Introduction to Probability
Interpretation of Probabilities
Understanding how to interpret probabilities is crucial. A probability of 1 (or 100%) means that the event is guaranteed to happen, while a probability of 0 (or 0%) means it cannot happen. Therefore, when evaluating whether a number can represent a probability, it is essential to consider its meaning in the context of possible outcomes.
Recommended video:
Introduction to Probability
Watch next
Master Introduction to Probability with a bite sized video explanation from Patrick
Start learningRelated Videos
Related Practice