Suppose the nightly rate for a hotel in Rome is thought to be bell-shaped and symmetrical with a mean of 138 euros and a standard deviation of 6 euros. The percentage of hotels with rates between 120 and 144 euros is

The percentage of hotels with rates between 120 and 144 euros is 84%.

Step-by-step explanation:

We know that the distribution of the nightly rate for a hotel in Rome is bell shaped with a mean of 138 euros and a standard deviation of 6 euros.

We want to know the proportion of hotels between 120 and 144 euros.

We can approximate the distribution to a normal distribution and calculate the z-score for both boundaries:

Then, we can calculate the proportion as the probability of having rates between 120 and 144:

Then, we can conclude that the percentage of hotels with rates between 120 and 144 euros is 84%.

step-by-step explanation:

no, her answer is not correct.   we square the lengths of all sides and then determine whether the pythagorean theorem holds here:

9² + 15² = 306.   this is not equal to the square of the longest side ( that square being 395.   answer c is correct.