Question

The lifespan of an LCD screen is approximately normally distributed with a mean of 6.2 years and a variance of 1.42. If the LCD screen is guaranteed for 2 years, what is the probability that an LCD screen sold will require replacement while still under guarantee?

Answer 1

Step-by-step explanation

We are given the following data:

`mean=6.2\text{ years}`

`variance=1.42`

So we can get the standard deviation as

`standard\text{ deviation=}√(1.42)=1.192`

The guaranteed number of years is 2 years

We will have

`z=\frac{x-mean}{standard\text{ deviation}}`

So, if the LCD is guaranteed to last for 2 years

Then, we will have our value of x as