<h2>
Answer:</h2>
Variance
<h2>
Step-by-step explanation:</h2>
The standard deviation is related to the variance. The standard deviation measures the variation or dispersion of a set of data and is represented by the Greek letter sigma
, while the variance measures how far a set of numbers are spread out from their average value. The variance is obtained by squaring the standard deviation, so the variance can be found as 
Answer:
The expression that represents his total time is given by "t = 7.5/s" where s is his speed against the wind.
Step-by-step explanation:
In order to solve this problem we will assign a variable to Curtis speed on the first leg of the trip, this will be called "s". Since the speed on the first part is "s" and the speed on the second part is 20% higher, then the speed on the second part is "1.2s". Each leg of the course is 9 miles long, therefore the time it took to go each way is given by:
time = distance/speed
First part:
t1 = 9/s
Second part:
t2 = 9/1.2s = 7.5/s
The expression for the whole course is the sum of each, so we have:
t = t1 + t2
t = 9/s + 7.5/s
t = (9 + 7.5)/s = (16.5)/s
I don’t understand your question.
10% is 90 1% is 9 90x4 is 360 add 9 is 369 nearest hundred is 400 i guess but the answer is deffinately 369