Three coins are tossed together. Find the probability of getting at least one head and one tail.

Given:

Three coins are tossed together.

To do:

We have to find the probability of getting at least one head and one tail.

Solution:

When three coins are tossed, the total possible outcomes are HHH, HHT, HTH, THH, TTH, THT, HTT and TTT.

This implies,

The total number of possible outcomes $n=8$.

Number of outcomes where at least one head and one tail occur $=6$   

Total number of favourable outcomes $=6$.

We know that,

Probability of an event $=\frac{Number\ of\ favourable\ outcomes}{Total\ number\ of\ possible\ outcomes}$

Therefore,

Probability of getting at least one head and one tail $=\frac{6}{8}$

$=\frac{3}{4}$

The probability of getting at least one head and one tail is $\frac{3}{4}$.