Advertisements
Advertisements
Question
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 less than $40,000?
Advertisements
Solution
Let x denotes the annual salaries of employees in a large company
Mean µ = 50,000 and S.D σ = 20,000
P(people earn less than $40,000) = P(X < 40,000)
When x = 40,000
z = `(40, 000 - 50, 000)/(20 000)`
= `(10,000)/(20,000)`
z = – 0.5
P(X < 40,000) = P(Z < – 0.5)
= P(`-oo` < z < 0) – P(– 0.5 < z < 0)
= 0.5 – P(– 0.5 < z <0)
= 0.5 – P(0 < z < 0.5) ......(Due to symmetry)
= 0.5 – 0.01915
= 0.3085
= P(X < 40,000) in percentage
= 0.3085 × 100
= 30.85
APPEARS IN
RELATED QUESTIONS
In a particular university 40% of the students are having newspaper reading habit. Nine university students are selected to find their views on reading habit. Find the probability that all those selected have newspaper reading habit
Out of 750 families with 4 children each, how many families would be expected to have atleast one boy
Out of 750 families with 4 children each, how many families would be expected to have children of both sexes? Assume equal probabilities for boys and girls.
Consider five mice from the same litter, all suffering from Vitamin A deficiency. They are fed a certain dose of carrots. The positive reaction means recovery from the disease. Assume that the probability of recovery is 0.73. What is the probability that atleast 3 of the 5 mice recover
Define Poisson distribution
Write the conditions for which the poisson distribution is a limiting case of binomial distribution
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).
Choose the correct alternative:
The parameters of the normal distribution f(x) = `(1/sqrt(72pi))"e"^(-(x - 10)^2)/72 - oo < x < oo`
Choose the correct alternative:
A manufacturer produces switches and experiences that 2 percent switches are defective. The probability that in a box of 50 switches, there are atmost two defective is :
Choose the correct alternative:
Forty percent of the passengers who fly on a certain route do not check in any luggage. The planes on this route seat 15 passengers. For a full flight, what is the mean of the number of passengers who do not check in any luggage?
