In this question, you should state clearly the values of the parameters of any normal distribution you use.
A supermarket sells two types of durians, D\(26\) and Civet King. The durians are sold by weight. The masses, in kilograms, of D\(26\) and Civet King are modelled as having normal distributions. The means and standard deviations of these distributions, and the selling prices, in \(\$\) per kilogram, are shown in the following table.
| Mean (kg) | Standard Deviation (kg) | Selling price (\(\$\) per kg) | |
|---|---|---|---|
| D26 | \(1.8\) | \(0.02\) | \(9\) |
| Civet King | \(\mu\) | \(\sigma\) | \(18\) |
Find the probability that the mass of a randomly selected D\(26\) is less than \(1.76\text{ kg}\).
[2]A customer buys \(4\) D\(26\) durians and \(3\) Civet King durians. Find the probability that the total cost of his purchase is more than \(\$160\).
[4]State an assumption needed for your calculations in part (iii).
[1]Need help? Join our JC Math tuition classes.
Learn more