Probability of at least one head in two coin tosses

MathematicsProbabilityEasy

Published: April 23, 2026

Question

Question 9 2 pts A coin is tossed twice. What is the probability that at least one head occurs?

Animated Video Solution

The first half plays free, the full solution is in the app.

Step 1

Let's find the probability of getting at least one head when a coin is tossed twice.

Step 2

First, let's list the sample space. A sample space represents all the possible outcomes of our experiment.

Step 3

When we toss a coin twice, we can get: Heads then Heads, Heads then Tails, Tails then Heads, or Tails then Tails.

S = \{HH, HT, TH, TT\}

Step 4

If we count them, we see there are four total outcomes in the sample space.

$$n(S) = 4$$

Step 5

Now, let's identify the favorable outcomes for our event. We want 'at least one head'.

Event E: At least one head occurs

5 more steps are locked. Watch the full animated, narrated solution for free.

Snap a photo, solve any question like this.

Free to download · First solutions are on us

100K+Questions solved daily

50K+Students learning

4.8 ★App Store rating