Answer:
the rate of change of the water depth when the water depth is 10 ft is; 
Step-by-step explanation:
Given that:
the inverted conical water tank with a height of 20 ft and a radius of 8 ft is drained through a hole in the vertex (bottom) at a rate of 4 ft^3/sec.
We are meant to find the rate of change of the water depth when the water depth is 10 ft.
The diagrammatic expression below clearly interprets the question.
From the image below, assuming h = the depth of the tank at a time t and r = radius of the cone shaped at a time t
Then the similar triangles ΔOCD and ΔOAB is as follows:
( similar triangle property)


h = 2.5r

The volume of the water in the tank is represented by the equation:



The rate of change of the water depth is :

Since the water is drained through a hole in the vertex (bottom) at a rate of 4 ft^3/sec
Then,

Therefore,

the rate of change of the water at depth h = 10 ft is:




Thus, the rate of change of the water depth when the water depth is 10 ft is; 
Answer:
9 miles
Step-by-step explanation:
You need to get 27 minutes to 81 minutes so you multiply 27 by 3, and that is 81, so you simply multiply 3 by 3 and get 9! Hope this helps! ;)
(27 x 3) = 81
(3 x3) = 9
Answer:
we can use division to solve real life problem such as: how much candy each of 5 students will receive if 20 candy are shared equally
Step-by-step explanation:
cause 20/5 = 4
Answer:
the answer should be x= -9 over 11
Step-by-step explanation: