Answer:
I think this could be the answer- x^ +2x-15
Answer:
Option C.
Step-by-step explanation:
We start with the expression:

where y > 0. (this allow us to have y inside a square root, so we don't mess with complex numbers)
We want to find the equivalent expression to this one.
Here, we can do the next two simplifications:

And:

If we apply these two to our initial expression, we can rewrite it as:


Here we can use the second simplification again, to rewrite:

So, concluding, we have:

Then the correct option is C.
Answer:
At least 202.44 mm in the top 15%.
Step-by-step explanation:
When the distribution is normal, we use the z-score formula.
In a set with mean
and standard deviation
, the zscore of a measure X is given by:

The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the pvalue, we get the probability that the value of the measure is greater than X.
In this question, we have that:

How many yearly mm of rainfall would there be in the top 15%?
At least X mm.
X is the 100-15 = 85th percentile, which is X when Z has a pvalue of 0.85. So X when Z = 1.037.




At least 202.44 mm in the top 15%.
123
+111 = 234 easy peasy you're welcome)