### Home > A2C > Chapter 7 > Lesson 7.1.2 > Problem7-27

7-27.

Flipping a penny and a nickel can be shown in a tree diagram. Use the tree diagram at right to calculate the following probabilities.

1. $P\left(H, T \right)$
(Note: This means the probability of getting one head and then one tail.)

Note that it says one head and then one tail, meaning that the head has to come first, and the tail second.

$\frac{1}{4}$

2. $P\left(T, H \right)$

See part (a).

3. $P\left(H, H\right)$ or $P\left(T, T \right)$

Is the probability of either event happening more likely or less likely than one event happening exclusively?