Chapter 13, Problem 39SGR

To determine

Calculate probability of P (red and then red) without replacement.

Answer to Problem 39SGR

Probability of finding red and then red without replacement is $\frac{28}{153}$

Explanation of Solution

Given:

No. of red marker=8

No. of green marker=5

No. of white marker = 5

Calculations:

Here, we have to calculate probability of finding blue white and again white marker in a box without any replacement.

Total number of markers =8+5+5=18

Probability of finding first red marker is,

  $P(firstred)=\frac{No.ofredmar\ker }{Totalno.ofmar\ker s}=\frac{8}{18}=\frac{4}{9}$

Probability of finding second red marker is,

  $P(\mathrm{Sec}ondred)=\frac{No.ofredmar\ker afterremovingoneredmar\ker }{Totalno.ofmar\ker afterremovingoneredmar\ker }=\frac{7}{17}$

Probability of finding red and then red marker is,

  $\begin{array}{l}P(redandthenred)=P(firstred)\times P(\mathrm{Sec}ondred)\\ =\frac{4}{9}\times \frac{7}{17}\\ =\frac{28}{153}\end{array}$

Conclusion:

Therefore, we are able to calculate probability of finding red and then red marker in a box.