Answer: E) Mean will decrease, standard deviation will decrease
Step-by-step explanation:
Initial mean = 81
Initial standard deviation = 9
New score = 78
Taking a look at the initial mean(averahe) score, which is 81 and the new score to be added to the initial scores, the initial average is greater than the new score. Hence, this will result in a decrease in the new mean score after adding the new score of 78.
Also, taking a look at the standard deviation which is 9, we can conclude that the variability in initial scores from the mean scores is high. However, the new score of 78 and the initial mean are very close, and tend to low variation. Hence, adding the new score will lead to a decrease in variability and hence a decrease in the value of standard deviation.
Answer:
The maximum revenue is $900, obtained with 30 people
Step-by-step explanation:
Naturally, the answer should be a number equal or higher than 20, because up to 20 persons, each one pays the same. Lets define a revenue function for x greater than or equal to 20.
f(x) = x*(40-(x-20)) = -x²+60x
Note that f multiplies the number of persons by how much would they pay (here, assuming that there are more than 20).
f is quadratic with negative main coefficient and its maximum value will be reached at the vertex.
The value of the x coordinate of the vertex is -b/2a = -60/-2 = 30
for x = 30, f(x) = 30*(40-(30-20))=30*30=900
So the maximum revenue is $900.
After clarification we see the respective diameters are


We're asked about the ratio

Now we can go through the choices.
A. If a = 4 and b = 6, then cell a is 100 times greater than cell b.

It would be more proper to say the diameter of cell A is 100 times the diameter of cell B, but yes, this is TRUE.
B. If a = 4 and b = 6, then cell b is 100 times greater than cell a.
FALSE. 10 to the minus 4 is 100 times bigger than 10 to the minus 6, so a is bigger.
C. If a = 4 and b = 6, then cell a is 2 times greater than cell b.
FALSE. We already calculated its 100 times bigger.
D. If a = 4 and b = 6, then cell b is 2 times greater than cell a.
FALSE.
Answer:
Quite simple. There are 52 weeks in a year. She gets paid 26 times, every other week.
38,350 / 26 = her salary from last year per check.
46,462 / 26 = her new salary per check
(46,462 - 38,350) / 26 = the difference per week
Let Monique's number of art brushes be m.
Then, since Chelsea has <span>11 times as many art brushes as Monique, Chelsea has 11m brushes.
Together they have 60 art brushes, so we write the equation:
m+11m=60.
This means that 12m=60, dividing both sides of the equation by 12 we get m=5.
Chelsea has 11m=11*5=55 brushes.
Answer: 55</span>