A particular type of tennis racket comes in sizes medium (M) and large (L).65% o

Question

A particular type of tennis racket comes in sizes medium (M) and large (L).65% of the customers at a store wants the large size racket. Customers for rackets arrive at the store one at a time. On any given day. what is the probability that it will be the 4th customer of the day before a large size is requested? P (that it will be the 4th customer of the day before a large size is requested.' Of the 15 randomly selected customers for rackets, what is the probability that at most 4 would ask for medium (M) size? P (at most 4 would ask for medium (M) size out of 15 customers) = Among 10 randomly selected customers, what is the probability that the number requesting large (L) rackets will be less than or equal to one stud deviation above the mean. The store currently has 7 large and 5 medium rackets. What is the probability that the next 10 customers will get their choice of racket size?

Explanation / Answer

Answer:

P(Large Racket) = 0.65

P(Medium Racket) = 1-0.65 = 0.35

To obtain the probability of that 4th customer will ask for 1st L size racket, we use negative binomial distribution which is the generalisation of geometric distribution. (i.e. first success is acheived at 4th trial)

P(4th customer asks for L size racket) = P(X=4) for k=1 = (0.65) * (0.35)^3 = 0.02786875

To find the prob of 4 customers out of 15 for M size, we use binomial distribution.

P(atmost 4 would ask for M size) = P(X<=4) = 0.3519

Related Questions

Navigate

• Browse (All)
• Browse A
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.