Advertisements
Advertisements
प्रश्न
The annual salaries of employees in a large company are approximately normally distributed with a mean of $50,000 and a standard deviation of $20,000. What percent of people earn more than $75,000
Advertisements
उत्तर
Let x denotes the annual salaries of employees in a large company
Mean µ = 50,000 and S.D σ = 20,000
Standard normal variate z = `(x - mu)/sigma`
P(people earn more than$75,000) = P(X > 70000)
When x = 75,000
z = `(75,000 - 50, 000)/(20,000)`
= `25000/20000`
= `5/4`
z = 1.25
P(X > 75,000) = P(X > 1.25)
= P(0 < z < `oo`) – P(0 < z < 1.25)
= 0.5 – 0.3944
= 0.1056
P(x > 750,000) in percent
= 01056 × 100
= 10.56
APPEARS IN
संबंधित प्रश्न
In a family of 3 children, what is the probability that there will be exactly 2 girls?
If the probability of success is 0.09, how many trials are needed to have a probability of atleast one success as 1/3 or more?
The distribution of the number of road accidents per day in a city is poisson with mean 4. Find the number of days out of 100 days when there will be no accident
Assuming that a fatal accident in a factory during the year is 1/1200, calculate the probability that in a factory employing 300 workers there will be at least two fatal accidents in a year, (given e-0.25 = 0.7788).
In a test on 2,000 electric bulbs, it was found that bulbs of a particular make, was normally distributed with an average life of 2,040 hours and standard deviation of 60 hours. Estimate the number of bulbs likely to burn for more than 2,150 hours
Time taken by a construction company to construct a flyover is a normal variate with mean 400 labour days and a standard deviation of 100 labour days. If the company promises to construct the flyover in 450 days or less and agree to pay a penalty of ₹ 10,000 for each labour day spent in excess of 450. What is the probability that the company pay a penalty of at least ₹ 2,00,000?
Choose the correct alternative:
The random variable X is normally distributed with a mean of 70 and a standard deviation of 10. What is the probability that X is between 72 and 84?
Choose the correct alternative:
A statistical analysis of long-distance telephone calls indicates that the length of these calls is normally distributed with a mean of 240 seconds and a standard deviation of 40 seconds. What proportion of calls lasts less than 180 seconds?
Choose the correct alternative:
The weights of newborn human babies are normally distributed with a mean of 3.2 kg and a standard deviation of 1.1 kg. What is the probability that a randomly selected newborn baby weight less than 2.0 kg?
X is a normally distributed variable with mean µ = 30 and standard deviation σ = 4. Find P(30 < X < 35)
