Chapter 13.6, Problem 35STP

To determine

To determine the probability.

Answer to Problem 35STP

Option D is correct.

Explanation of Solution

Given information :

  

Total possibilities are 10+6+3+1 = 20

We have to determine the probability that the first customer wins manicure or a massage,

Probability that customer gets manicure is $\frac{10}{20}=\frac{1}{2}$

Probability that customer gets massage is $\frac{3}{20}$

Now,

P(manicure or massage) $=\frac{1}{2}+\frac{3}{20}=\frac{13}{20}$ or 0.65

Hence option D is correct.