Help with statistics! How do I set this up? "Assume that the average life of a color TV is 8.2 years with a standard deviation of 1.3 years before it breaks. Suppose that a company guarantees color TVs and will replace a TV that breaks while under guarantee with a new one. However, the company does not want to replace more than 15% of the TVs under guarantee. For how long should the guarantee be made (rounded to the nearest tenth of a year)?"

Question

amistre64 · Answer

mean is 8.2,  sd = 1.3

determine the z value for 15%

amistre64 · Answer

$$z=\frac{x-mean}{sd}$$
$$z(sd)+mean=x$$

amistre64 · Answer

im thinking we can do a one tailed run for it .... to find the shortest 15%

amistre64 · Answer

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