1. The life time of a certain brand of bulbs produced by a company is normally distributed, with mean 210 hours and standard deviation 56 hours. What is the probability that a bulb picked at random from this company’s products will have a life time of:
(i) at least 300 hours,
(ii) at most 100 hours,
(iii) between 150 and 250 hours.
1. The life time of a certain brand of bulbs produced by a company is normally...
Suppose that the life expectancy of a certain brand of non defective light bulbs is normally distributed, with a mean life of 1300 hr and a standard deviationof 150 hr. If 30,000 of these bulbs are produced, how many can be expected to last at least 1300 hr? light bulbs?
Suppose a brand of light bulbs is normally distributed, with a mean life of 1700 hr and a standard deviation of 150 hr. Find the probability that a light bulb of that brand lasts between 1415 hr and 1910 hr.
The life expectancy of a particular brand of light bulbs is normally distributed with a mean of 1500 hours and a standard deviation of 75 hours. What is the probability that a bulb will last between 1500 and 1650 hours?
The life of light bulbs is distributed normally. The standard deviation of the lifetime is 15 hours and the mean lifetime of a bulb is 580 hours. Find the probability of a bulb lasting for at least 590 hours. Round your answer to four decimal places.
Question 4 (2 points) The lifetimes of a certain brand of light bulbs are known to be normally distributed with a mean of 1,500 hours and a standard deviation of 400 hours. A random sample of 64 of these light bulbs is taken. The probability is 0.15 that the sample mean lifetime is more than how many hours? 1) 1670 2) 1548 3) 1552 4) 1652
Please show all your work. 4 Light Bulbs The lifetimes of light bulbs produced by a c mean 1000 hours and standard deviation 100 hours. ompany are independent and normally distributed with (a) What is the probability that a bulb will last less than 800 hours? (b) What is the probability that a bulb will last at least 1200 hours? (c) If 2 new bulbs are installed at the same time, what is the probability that they will both still...
The mean life of a particular brand of light bulb is 1200 hours and the standard deviation is 75 hours. Tests show that the life of the bulb is approximately normally distributed. What is the range of hours that approximately 68% of the bulbs will last?
The life of light bulbs is distributed normally. The variance of the lifetime is 400400 and the mean lifetime of a bulb is 600600 hours. Find the probability of a bulb lasting for at most 633633 hours. Round your answer to four decimal places.
The life of light bulbs is distributed normally. The variance of the lifetime is 625 and the mean lifetime of a bulb is 510 hours. Find the probability of a bulb lasting for at most 527 hours. Round your answer to four decimal places.
The life of light bulbs is distributed normally. The variance of the lifetime is 625 and the mean lifetime of a bulb is 570 hours. Find the probability of a bulb lasting for between 532 and 599 hours. Round your answer to four decimal places.