A manufacturer supplies DVD players to tetailers in batches of 20. Over the past 12 months the manufacturer had 30% of the players returned because they were faulty. (a) Give two reasons why a binomial distribution may be a suitable model for the numb of faulty DVD players in a batch. (b) Find the probability that a random batch of DVD players supplied by this manufacturer contains (i) (1) no faulty DVD players more than 4 faulty DVD players. (c) Find the mean and variance of the number of faulty DVD players in a batch

A First Course in Probability (10th Edition)
10th Edition
ISBN:9780134753119
Author:Sheldon Ross
Publisher:Sheldon Ross
Chapter1: Combinatorial Analysis
Section: Chapter Questions
Problem 1.1P: a. How many different 7-place license plates are possible if the first 2 places are for letters and...
Question
only 1st
1. A manufacturer supplies DVD players to retailers in batches of 20. Over the past 12
months the manufacturer had 30% of the players returned because they were faulty.
(a) Give two reasons why a binomial distribution may be a suitable model for the number
of faulty DVD players in a batch.
(b) Find the probability that a random batch of DVD players supplied by this
manufacturer contains
no faulty DVD players.
more than 4 faulty DVD players.
(i)
(ii)
(c) Find the mean and variance of the number of faulty DVD players in a batch.
The company considered this unacceptable and introduced a new quality control strategy
aiming to reduce the number of faulty DVD players.
One month after the new strategy, a random batch of 20 DVD players was inspected and 4
were found faulty.
(d) Write down suitable hypotheses and carry out a hypothesis test at the 5 % level to
determine whether there is evidence to suggest that this is correct.
2. Two teams, Realers and Senlers, meet for a quiz night. From past results it seems that in
years Realers win, the probability of winning the next year is 0.7 when the Settlers win
the probability of them winning is 0,5. It is not possible for the quiz to end in a druw.
The Realers won the quiz in 2016.
a. Draw a probability tree diagram for the first three years up to 2019.
b. Find the probability that the Settlers will win in 2019.
3. A group of 50 students were asked which of three textbooks, Management (M),
Quantitative Methods (Q) or English (E) they read daily. The responds showed that 25
read M,16 read Q. 14 read E, 5 read both M and Q. 4 read both Q and E, 6 read both E
and M and 2 read all 3.
a. Represent these data on a Venn diagram.
Find the probability that a student selected at random from this group reads:
b. At least I of the textbooks daily.
c. Only I of the textbooks.
d. Only Management textbooks.
Transcribed Image Text:1. A manufacturer supplies DVD players to retailers in batches of 20. Over the past 12 months the manufacturer had 30% of the players returned because they were faulty. (a) Give two reasons why a binomial distribution may be a suitable model for the number of faulty DVD players in a batch. (b) Find the probability that a random batch of DVD players supplied by this manufacturer contains no faulty DVD players. more than 4 faulty DVD players. (i) (ii) (c) Find the mean and variance of the number of faulty DVD players in a batch. The company considered this unacceptable and introduced a new quality control strategy aiming to reduce the number of faulty DVD players. One month after the new strategy, a random batch of 20 DVD players was inspected and 4 were found faulty. (d) Write down suitable hypotheses and carry out a hypothesis test at the 5 % level to determine whether there is evidence to suggest that this is correct. 2. Two teams, Realers and Senlers, meet for a quiz night. From past results it seems that in years Realers win, the probability of winning the next year is 0.7 when the Settlers win the probability of them winning is 0,5. It is not possible for the quiz to end in a druw. The Realers won the quiz in 2016. a. Draw a probability tree diagram for the first three years up to 2019. b. Find the probability that the Settlers will win in 2019. 3. A group of 50 students were asked which of three textbooks, Management (M), Quantitative Methods (Q) or English (E) they read daily. The responds showed that 25 read M,16 read Q. 14 read E, 5 read both M and Q. 4 read both Q and E, 6 read both E and M and 2 read all 3. a. Represent these data on a Venn diagram. Find the probability that a student selected at random from this group reads: b. At least I of the textbooks daily. c. Only I of the textbooks. d. Only Management textbooks.
Expert Solution
steps

Step by step

Solved in 2 steps

Blurred answer
Recommended textbooks for you
A First Course in Probability (10th Edition)
A First Course in Probability (10th Edition)
Probability
ISBN:
9780134753119
Author:
Sheldon Ross
Publisher:
PEARSON
A First Course in Probability
A First Course in Probability
Probability
ISBN:
9780321794772
Author:
Sheldon Ross
Publisher:
PEARSON