Chapter 13.4, Problem 19E

To determine

To find the probability of taking $2$ blue notebooks.

Answer to Problem 19E

Dependent, $\frac{2}{7}$

Explanation of Solution

Given:

A shell of $4$ blue notebooks and $3$ black notebooks.

Calculation:

The events are dependent because outcome of one eventaffects the outcome of another event.

Let A be the event of drawingfirst blue notebooks

Let B be the event of drawingsecond blue notebooks.

Total sample space $=7$

Therefore probability of event A is $P(A)=\frac{4}{7}$

Therefore probability of event B is $P(B)=\frac{3}{6}=\frac{1}{2}$

Hence,

  $\begin{array}{l}P(A\text{ and }B)=P(A)\times P(B)\\ P(A\text{ and }B)=\frac{4}{7}\times \frac{1}{2}=\frac{2}{7}\end{array}$