Answer:

Step-by-step explanation:
Assuming a mean of $204 per night and a deviation of $55.
a. What is the probability that a hotel room costs $225 or more per night (to 4 decimals)?
Normal distribution, is a "probability distribution that is symmetric about the mean, showing that data near the mean are more frequent in occurrence than data far from the mean"
The Z-score is "a numerical measurement used in statistics of a value's relationship to the mean (average) of a group of values, measured in terms of standard deviations from the mean".
Let X the random variable that represent the cost per night at the hotel, and for this case we know the distribution for X is given by:
Where
and 
And let
represent the sample mean, the distribution for the sample mean is given by:

We are interested on this probability

And the best way to solve this problem is using the normal standard distribution and the z score given by:

If we apply this formula to our probability we got this:


And we can find this probability on this way:

F twice the 1st number minus 3 times the second number is 26<span>, </span>find both<span> ... </span>Twice the first number<span> is eleven more than </span>the sum<span> of the other </span>two numbers<span>.</span>
Answer:
B 9/10
Step-by-step explanation:
1/5 is equivalent to 2/10.
then just add the numerators.
A unit rate simply means how many of one type of units you get per 1 other type of unit.
Examples of that:

This is rate of fluid flow of some pump for example. It pumps 300 liters every second.
Other example:

This is example for speed. Somebody is moving at 50 kilometers per hour (every hour he travels 50 kilometers)