math

posted by .

in a shipment of 20 computers, 3 are defective

three computers are randomly selected and tested. what is the probability that all 3 are defective if the first and second ones are not replaced after being tested.

a. 1/760
b.1/1140
c.27/8000
d.3/5000

i chose D, is this correct

• math -

First one 3/20
Second one 2/19
third one 1/18
3/20*2/19*1/18 = 1/(3*20*19) =1/1140

• math -

The answer is B Explanation: 3/20*2/19*1/18=1/(3*20*19)=1/1140

• math -

yffffff'

Similar Questions

1. statistics

A shipment of 30 computers contains four that are defective. How many ways can a small business buy five of these computers and receive no defective ones
2. statistics

In a box of thirty AAA batteries, there are three defective batteries. Two batteries are randomly selected and tested. What is the probability that both are defective, if the first one is not replaced after being tested?
3. statistics 221

A shipment of 35 computers contains three that are defective. How many ways can a small business buy four of these computers and receive no defective ones. a. 128 b. 35960 c. 52360 d. 6545
4. EEE

the solve of the shipment of 10 items has 2 items defective and 8 items are non defective.IN THE inspection of the shipment a sample of items will be selected and tested.if a defective items is found the shipment of 10 items will rejected.in …
5. Statistics

A shipment of portable radios contains 14 good radios and 3 defective ones. If two are randomly selected (without replacement) and tested, find the probability that at least one will be defective.
6. Statistics

A shipment of portable radios contains 14 good radios and 3 defective ones. If two are randomly selected (without replacement) and tested, find the probability that at least one will be defective.
7. math

In a shipment of 50 calculators,4 are defective. Two calculators are randomly selected and tested. What is the probability that both are defective if the first one is not replaced after being tested?
8. statistics and probability

A shipment of 20 computers contains 4 defective machines.Two computers are selected at random without replacement and tested for being detective. (a). is this a binomial experiment?
9. stats

shipment of 30 computers, 8 are defective. Four computers are chosen at random. Find the probability that: a)Exactly two are defective b)None are defective c)At most two are defective
10. math

500bottles contains 10 bottles that are defective.3bottles are selected,random,without replacement.a)what is the probability that the third one selected is defective given that the first was okay and second one selected was defective?

More Similar Questions

Post a New Question