Remove parentheses
2/5 • d-10 - 2/3 • d+6
calculate
2/5d-4 - 2/3d-4
the answer
-4/15d-8
Answer:
66 minutes, or 1 hour and 6 minutes.
Step-by-step explanation:
let us first do the rectangular aquarium:
8 x 10 = 80
80 x 14 = 1120
now the second box
23 x 25 = 575
575 x 33 = 18975
we can divide the boxes volume:
18975/575 = 33
so all we have to do is times 33 by 2 which equals:
66 minutes, or 1 hour and 6 minutes.
A. Total Revenue (R) is equal to price per dive (P) multiplied by number of customers (C). We can write
.
Per price increase is $20. So four price increase is $
. Hence, price per dive is 100+80=$180.
Also per price increase, 2 customers are reduced from 30. For 4 price increases,
customers are reduced. Hence, total customers is
.
So Total Revenue is:

B. Each price increase is 20. So x price increase is 20x. Hence, new price per dive would be equal to the sum of 100 and 20x.
Also per price increase, customers decrease by 2. So per x price increases, the customer decrease is 2x. Hence, new number of customers is the difference of 30 and 2x.
Therefor we can write the quadratic equation for total revenue as the new price times the new number of customers.

C. We are looking for the point (x) at which the equation modeled in part (B) gives a maximum value of revenue (y). That x value is given as
, where a is the coefficient of
and b is the coefficient of x. So we have,

That means, the greatest revenue is achieved after 5 price increases. Each price increase was 20, so 5 price increase would be
. So the price that gives the greatest revenue is
.
ANSWERS:
A. $3960
B. 
C. $200
F(4)=4(4)+5
Which equals
F(4)=21
To find the total of 3/4 and 4/5 is to add them together. However, in order to add them together you need to find the least common denominator (LCD). And the LCD of both denominators would be 20, because that is the smallest number both 4 and 5 can divide into. And here is the tricky part, now you have to change the numerators. So since 3/4th's now has a denominator of 20 you have to make the 3 match the 20. So 4 times what it 20? It is 5. So now multiply 5 by three and that will give you 15/20, which can reduce to 3/4 which means that you did this correctly! Now repeat the same steps with 4/5:
4/5=4/20
20÷5=4
4•4=16
16/20 (16/20 can reduce to 4/5 which means you did this correctly.
Now to add them keep the denominators the same and only add the numerators:
15/20 + 16/20 = 31/20
Now this as a mixed number would be 1 11/20. I hope this was helpful!