Table of contents

1. Introduction to Statistics53m
2. Describing Data with Tables and Graphs2h 1m
3. Describing Data Numerically1h 48m
4. Probability2h 26m
5. Binomial Distribution & Discrete Random Variables2h 55m
6. Normal Distribution & Continuous Random Variables1h 48m
7. Sampling Distributions & Confidence Intervals: Mean2h 8m
8. Sampling Distributions & Confidence Intervals: Proportion1h 20m
- Sampling Distribution of Sample Proportion
  35m
- Confidence Intervals for Population Proportion
  45m
9. Hypothesis Testing for One Sample2h 23m
10. Hypothesis Testing for Two Samples3h 25m
11. Correlation1h 6m
12. Regression1h 4m
13. Chi-Square Tests & Goodness of Fit1h 30m
14. ANOVA1h 4m

4. Probability

Basic Concepts of Probability

Statistics for Business

4. Probability

Basic Concepts of Probability

Previous problemNext problem

Struggling with Statistics for Business?

Join thousands of students who trust us to help them ace their exams!Watch the first video

Multiple Choice

If the probability of an event is 20%, what is the expected number of times the event will occur in 90 independent trials?

Previous problemNext problem

Verified step by step guidance

Step 1: Understand the concept of expected value. The expected value in probability is calculated as the product of the probability of an event and the number of trials. It represents the average number of occurrences of the event over a large number of trials.

Step 2: Identify the given values in the problem. The probability of the event occurring is 20%, which can be expressed as 0.2 in decimal form. The number of independent trials is 90.

Step 3: Write the formula for expected value. The formula is:

E = p \times n

, where

E

is the expected value,

p

is the probability of the event, and

n

is the number of trials.

Step 4: Substitute the given values into the formula. Replace

p

with 0.2 and

n

with 90 in the formula.

Step 5: Multiply the probability (0.2) by the number of trials (90) to calculate the expected value. This will give the average number of times the event is expected to occur in 90 trials.