Answer:
18 units
Step-by-step explanation:
The centroid is located 1/3 the distance from the midpoint of a side to the opposite vertex. That means ...
CG = 2·DG = 6 + DG
Then
DG = 6 . . . . . . subtract DG from the above equation
Of course, ...
CD = CG +DG = 2·6 +6
CD = 18
1/9 + 1/2 = 1/x
Let x = length of time it will take both hoses to work together
Multiply both sides by 18x.
2x + 9x = 18
10x = 18
x = 18/10
x = 9/5
x = 1.8 hours
In other words, if both hoses work together, the pool can be filled in 1 hour and 48 minutes.
The answer to your problem is a+6x+5.
2.5 b = 27.5
b = 27.5 / 2.5
b = 11
