Answer :
Given inf :
The population mean $(μ) = 260$
The population standard deviation $(σ) = 50$
Solution :
The percentage of the students would have book costs that exceeded 460 dollars :
$$\therefore P(x > 460) = P\left( \frac{x – \mu}{\sigma} > \frac{460 – 260}{50} \right)$$ $$= P(z > 4)$$ $$\approx 0.003\%$$
