Question

In: Statistics and Probability

2. The lifetime of a SuperTough AAA battery is normally distributed with mean = 28.5 hours...

2. The lifetime of a SuperTough AAA battery is normally distributed with mean = 28.5 hours and standard deviation = 5.3 hours. For a battery selected at random, what is the probability that the lifetime will be

  1. 25 hours or less

  2. 34 hours or more

  3. Between 25 and 34 hours

Solutions

Expert Solution


Related Solutions

The lifetime of a certain battery is normally distributed with a mean value of 20 hours...
The lifetime of a certain battery is normally distributed with a mean value of 20 hours and a standard deviation of 2.5 hours. a. What are the distribution parameters (μ and σ) of the sample mean if you sample a four pack of batteries from this population? b. If there are four batteries in a pack, what is the probability that the average lifetime of these four batteries lies between 18 and 20? c. What happens to the probability in...
The lifetime of a certain type of battery is normally distributed with a mean of 1000...
The lifetime of a certain type of battery is normally distributed with a mean of 1000 hours and a standard deviation of 100 hours. Find the probability that a randomly selected battery will last between 950 and 1000 (round answers to three decimal places, example 0.xxx)? The lifetime of a certain type of battery is normally distributed with a mean of 1000 hours and a standard deviation of 100 hours. Find the probability that a randomly selected battery will last...
2. The lifetime of light bulb is normally distributed with mean of 1400 hours and standard...
2. The lifetime of light bulb is normally distributed with mean of 1400 hours and standard deviation of 200 hours. a. What is the probability that a randomly chosen light bulb will last for more than 1800 hours? b. What percentage of bulbs last between 1350 and 1550 hours? c. What percentage of bulbs last less than 1.5 standard deviations below the mean lifetime or longer than 1.5 standard deviations above the mean? d. Find a value k such that...
The lifetime of a semiconductor laser is normally distributed with a mean of 7000 hours and...
The lifetime of a semiconductor laser is normally distributed with a mean of 7000 hours and a standard deviation of 600 hours. A product contains three lasers, and the product fails if any of the laser fails. Assuming that the lasers fail independently, would the product lifetime exceed 10,000 hours of use before failure with a probability of 99%. If not, recommend a n alternative lifetime distribution for the lasers.
The lifetime of light bulb is normally distributed with mean of 1400 hours and standard deviation of 200 hours.
The lifetime of light bulb is normally distributed with mean of 1400 hours and standard deviation of 200 hours. a. What is the probability that a randomly chosen light bulb will last for more than 1800 hours? b. What percentage of bulbs last between 1350 and 1550 hours? c. What percentage of bulbs last less than 1.5 standard deviations below the mean lifetime or longer than 1.5 standard deviations above the mean? d. Find a value k such that 20% of the bulbs last...
Suppose LCD screens have lifetimes that are normally distributed with a mean lifetime of 18000 hours...
Suppose LCD screens have lifetimes that are normally distributed with a mean lifetime of 18000 hours with a variance of 1000000 hours. (a) Find the probability a screen lifetime is under 15000 hours. (b) Find the probability a lifetime is between 15000 and 20000 hours. (c) The top 10% of lifetimes will be at least how long? Please show all work for review
the lifetime of a certain battery has an unknown distribution with mean value 8 hours and...
the lifetime of a certain battery has an unknown distribution with mean value 8 hours and a standard deviation of 2 hours. what is the probability that the average battery lifetime of a sample of 36 batteries will be greater than 8.1 hours? I know by the CLT that at 36 trials the sample mean will follow a normal distribution but i cant remember how to calculate the variance of this distribution nor do i know where to go from...
The lifetime of a certain kind of battery is exponentially distributed, with an average lifetime of...
The lifetime of a certain kind of battery is exponentially distributed, with an average lifetime of 25 hours 4. Find the value of the 60th percentile for the lifetime of one battery. Remember units! 5. Write an interpretation (a sentence) of the 60th percentile for the lifetime of one battery. Your interpretation should include the value of the 60th percentile with correct units. 6. We are interested in the average lifetime of 16 of these batteries. Call this random variable....
The lifetime of a certain brand of lightbulbs is normally distributed with the mean of 3800...
The lifetime of a certain brand of lightbulbs is normally distributed with the mean of 3800 hours and standard deviation of 250 hours. The probability that randomly selected lightbulb will have lifetime more than 3500 hours is ________ The percent of lightbulbs which have the lifetime between 3500 and 4200 hours is __________ What lifetime should the manufacturer advertise for these lightbulbs if he assumes that 10% of lightbulbs with the smallest lifetimes will burn out by that time? Advertised...
1)The life in hours of a battery is known to be approximately normally distributed, with standard...
1)The life in hours of a battery is known to be approximately normally distributed, with standard deviation 1.25 hours. A random sample of 10 batteries has a mean life of 40.5 hours. A. Is there evidence to support the claim that battery life exceeds 40 hours ? Use α= 0.05. B. What is the P-value for the test in part A? C. What is the β-error for the test in part A if the true mean life is 42 hours?...
ADVERTISEMENT
ADVERTISEMENT
ADVERTISEMENT