Ask question

Ask question

All categories

olya-2409 [2.1K]

2 years ago

5

Printed circuit cards are placed in a functional test after being populated with semiconductor chips. A lot contains 140 cards,

and 20 are selected without replacement for functional testing. a) If 20 cards are defective, what is the probability that at least 1 defective card is in the sample? b) If 5 cards are defective, what is the probability that at least 1 defective card appears in the sample?

1 answer:

hjlf2 years ago

8 0

Answer:

a) 0.9644 or 96.44%

b) 0.5429 or 54.29%

Step-by-step explanation:

a) The probability that at least 1 defective card is in the sample P(A) = 1 - probability that no defective card is in the sample P(N)

P(A) = 1 - P(N) .....1

Given;

Total number of cards = 140

Number selected = 20

Total number of defective cards = 20

Total number of non defective cards = 140-20 = 120

P(N) = Number of possible selections of 20 non defective cards ÷ Number of possible selections of 20 cards from all the cards.

P(N) = 120C20/140C20 = 0.0356

From equation 1

P(A) = 1 - 0.0356

P(A) = 0.9644 or 96.44%

b) Using the same method as a) above

P(A) = 1 - P(N) .....1

Given;

Total number of cards = 140

Number selected = 20

Total number of defective cards = 5

Total number of non defective cards = 140-5 = 135

P(N) = 135C20/140C20 = 0.457

From equation 1

P(A) = 1 - 0.4571

P(A) = 0.5429 or 54.29%

You might be interested in

Mr. Chang’s class has 28 students, 4/7 of whom are girls. Which equation shows how to determine the number of girls in Mr. Chang

mars1129 [50]

Answer:

b

Step-by-step explanation:

6 0

2 years ago

Read 2 more answers

Robert makes $951 gross income per week and keeps $762 of it after tax withholding. How many allowances has Robert claimed? For

MAXImum [283]

Answer:

Option D,four is correct

Step-by-step explanation:

The tax withholding from the gross income of $951 is the gross income itself minus the income after tax withholding i.e $189 ($951-$762)

The percentage of the withholding =189/951=20% approximately

Going by the multiple choices provided,option with 4,189 dollars seems to the correct option as that is the exact of the tax withholding on Robert's gross income and his earnings fall in between $950 and $960

4 0

2 years ago

A store is selling 5 cans of tomato sauce for $4.50. What is the unit price?

NARA [144]

Hi there! The answer is $0.90

To find the price per unit we must divide the total amount of money by the amount of units sold. So we get the following:
$4.50 / 5 = $0.90

4 0

2 years ago

Read 2 more answers

Kenneth has entered a check payment of $350.25 in his checkbook. If the old balance was $545.95, what is his latest balance?

Rama09 [41]

Just add the new paycheck to the old balance:
350.25 + 545.95 = $896.2

5 0

2 years ago

Read 2 more answers

In choice situations of this type, subjects often exhibit the "center stage effect," which is a tendency to choose the item in t

victus00 [196]

Complete Question

The complete question is shown on the first uploaded image

Answer:

a

The probability that he or she would choose the pair of socks in the center position is $p =\frac{1}{5}$

The correct answer choice is

X has a binomial distribution with parameters n=100 and p=1/5

b

The mean is $\mu = 20$

The standard deviation is $\sigma=4$

c

The probability, $P =0.0002$

d

The correct answer is

The experiment supports the center stage effect. If participants were truly picking the socks at random, it would be highly unlikely for 34 or more to choose the center pair.

Using the R the probability $Pe = 0.0003$

The probabilities $P \approx Pe$

Step-by-step explanation:

Since the person selects his or her desired pair of socks at random , then the probability that the person would choose the pair of socks in the center position from all the five identical pair is mathematically evaluated as

$p =\frac{1}{5}$

$=0.2$

The mean of this distribution is mathematical represented as

$\mu = np$

substituting the value

$\mu = 100 * 0.2$

$\mu = 20$

The standard deviation is mathematically represented as

$\sigma = \sqrt{np (1-p)}$

substituting the value

$= \sqrt{100 * 0,2 (1-0.2)}$

$\sigma=4$

Applying normal approximation the probability that 34 or more subjects would choose the item in the center if each subject were selecting his or her preferred pair of socks at random would be mathematically represented as

$P=P(X \ge 34 )$

By standardizing the normal approximation we have that

$P(X \ge 34) \approx P(Z \ge z)$

Now z is mathematically evaluated as

$z = \frac{x-\mu}{\sigma }$

Substituting values

$z = \frac{34-20}{4}$

$=3.5$

So using the z table the $P(Z \ge 3.5)$ is 0.0002

The probability P and Pe that 34 or more subject would choose the center pair is very small So

The correct answer is

The experiment supports the center stage effect. If participants were truly picking the socks at random, it would be highly unlikely for 34 or more to choose the center pair.

6 0

2 years ago