7. The life of a Freeze Breeze electric fan is normally distributed with a mean 4 years and standard deviation 1.2 years. The manufacturer will replace any defective fan free of charge while it is under guarantee. For how many years should a Freeze Breeze fan be guaranteed if the manufacturer does not want to replace more than 5% of them?
7. The life of a Freeze Breeze electric fan is normally distributed with a mean 4...
If the lifetime X of a certain kind of automobile battery is normally distributed with mean of 3 years and standard deviation of 1 year, and the manufacturer wishes to guarantee the battery for 2 years, what percentage of the batteries will he have to replace under the guarantee? 5.
A certain type of refrigerator has a length of life that is approximately normally distributed with a mean of 4.8 years and a population standard deviation of 1.3 years. What period of time should the manufacturer give as a guarantee if it is willing to replace only 1% of the machines?
4. A manufacturer knows that their items have a normally distributed lifespan, with a mean of 14.4 years, and standard deviation of 3.2 years. If you randomly purchase 21 items, what is the probability that their mean life will be longer than 15 years? (Give answer to 4 decimal places.) 5. A particular fruit's weights are normally distributed, with a mean of 704 grams and a standard deviation of 12 grams. If you pick 12 fruit at random, what is...
The average life of a certain type of small motor is 10 years with a standard deviation of 2 years. The manufacturer replaces free all motors that fail while under guarantee. If she is willing to replace 3% of the motors that fail, how long a guarantee (in years) should she offer? You may assume that the lives of the batteries are normally distributed. A properly labeled figure of the normal distribution curve and x and z values is required...
A mechanic sells a brand of automobile tire that has a life expectancy that is normally distributed, with a mean life of 29 comma 000 miles and a standard deviation of 2800 miles. He wants to give a guarantee for free replacement of tires that don't wear well. How should he word his guarantee if he is willing to replace approximately 10% of the tires? Tires that wear out by [ ] miles will be replaced free of charge. (Round...
The life span of a box turtle are normally distributed with a mean of 180 years and a standard deviation of 40 years. a) What is the probability that a turtle will live for under 50 years? b) If there are 750 of these turtles in captivity, how many will live between 100 and 250 years?
Mechanic sells a brand of automobile tire that has a life expectancy that is normally distributed, with a mean life of 27,000 miles and a standard deviation of 2200 miles. He wants to get into a free replacement of tires That don’t wear well. How Should he word his guarantee if he is willing to replace approximately 10% of the tires?Tires that wear out by miles will be replaced free of charge. (Round to the nearest mile as needed.)
(5 points) The life of an electric transistor is normally distributed, with a mean of 500 hours and a standard deviation of 80 hours. Determine the probability the transistor wil last more than 400 hours. 3.
5. A particular fruit's weights are normally distributed, with a mean of 704 grams and a standard deviation of 12 grams. If you pick 12 fruit at random, what is the probability that their mean weight will be between 692 grams and 701 grams (Give answer to 4 decimal places.) 6. A particular fruit's weights are normally distributed, with a mean of 286 grams and a standard deviation of 18 grams. If you pick 25 fruit at random, what is...
A mechanic sells a brand of automobile tire that has a life expectancy that is normally distributed, with a mean life of 30,000 miles and a standard deviation of 2800 miles. He wants to give a guarantee for free replacement of tires that don't wear well. How should he word his guarantee if he is willing to replace approximately 10% of the tires?