normal distribution strange probability

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Given the particular normal distribution specified below, what is the probability that a random observation falls within the specified range .004 greater and less than the average?

original Lower limit is .496

original upper limit is .504

$$\mu = .500$$ defective equipment cause the average to change to $$\mu = .449$$

$$\sigma = .002$$

new Lower limit is .445

new upper limit is .453

So how do you compensate for your average changing because of defective equipment?


OLD info When I use my ti 89 normal cdf function I get 2.24 which isn't even a probability. Is there something special I need to do because my average changes or is there something special about these numbers?

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If $\mu=0.5$ and $\sigma=0.002$, $P(0.496<X<0.504)=P(\frac{0.496-0.5}{0.002}<Z<\frac{0.504-0.5}{0.002})=\Phi(2)-\Phi(-2)\approx 0.9545$, where $Z$ is the standard normal r.v. and $\Phi(\cdot)$ its cumulative density function.

If $\mu=0.499$ and $\sigma=0.002$, $P(0.496<X<0.504)=P(\frac{0.495-0.499}{0.002}<Z<\frac{0.503-0.499}{0.002})=\Phi(2)-\Phi(-2)\approx 0.9545$.