trigonometry
posted by Rob .
suppose a manufacterer of transistors believes that, on the average, one defective transistor occurs in every 100 transistors.
a. find the probability that a batch of 20 transistors has 2 defectives.
b. find the probability that a batch of 20 transistors has at most 2 defectives.
You can use something called the binomial probability function for these kinds of problems.
The function is this:
P(x) = (nCx)(p^x)[q^(nx)]
For a:
n = 20
p = 1/100 = .01
q = 1  p = 1  .01 = .99
Substituting:
P(2) = (20C2)(.01^2)(.99^18) = (190)(.0001)(.8345) = .0159
For b:
n = 20
p = .01
q = .99
x = 0, 1, 2
Find P(0), P(1), and P(2). Add all values together for your probability.
I hope this helps.
Respond to this Question
Similar Questions

System of Linear Equations
A manufacturer produces three types of radios: deluxe, standard and economy. Each radio uses three different types of transistors: P, Q and R. The deluxe radio uses 2 P's, 7 Q's and 1 R. The standard contains 2 P's, 3 Q's and 1 R, … 
MATH
A manufacturer produces three types of radios: deluxe, standard and economy. Each radio uses three different types of transistors: P, Q and R. The deluxe radio uses 2 P's, 7 Q's and 1 R. The standard contains 2 P's, 3 Q's and 1 R, … 
MATH please help!
A manufacturer produces three types of radios: deluxe, standard and economy. Each radio uses three different types of transistors: P, Q and R. The deluxe radio uses 2 P's, 7 Q's and 1 R. The standard contains 2 P's, 3 Q's and 1 R, … 
math
A manufacturer produces three types of radios: deluxe, standard and economy. Each radio uses three different types of transistors: P, Q and R. The deluxe radio uses 2 P's, 7 Q's and 1 R. The standard contains 2 P's, 3 Q's and 1 R, … 
A2T
From 19711995 avg # transistors modeled by n=2300(1.07)^t, where t is # of years since 1971. Estimate # of transistors in 1998 (round to nearest integer) Does anyone know how to set up this equation? 
A2T
From 19711995 avg # transistors modeled by n=2300(1.07)^t, where t is # of years since 1971. Estimate # of transistors in 1998 (round to nearest integer) Does anyone know how to set up this equation? 
Math
Gordon Moore stated that the number of transistors that can be placed on an integrated circuit will double every 2 years. This trend is known as Moore's Law. In 1978, the Intel 8086 held 29,000 transistors on an integrated circuit. … 
Math
3.22 Defective rate. A machine that produces a special type of transistor (a component of computers) has a 2% defective rate. The production is considered a random process where each transistor is independent of the others. (a) What … 
Math 120
A box contains 10 â€‹transistors,4 of which are defective. If 4 are selected atâ€‹ random, find the probability that a. All are defective. b. None are defective. 
math/statistics
From a shipment of 65 transistors, 4 of which are defective, a sample of 6 transistors is selected at random. (a) In how many different ways can the sample be selected?