The radius of a right circular cylinder is increasing at the rate of 7 in./s, while the height is decreasing at the rate of 3 in./s. At what rate is the volume of the cylinder changing when the radius is 17 in. And the height is 5 in.?

1014.73 in³/s

Step-by-step explanation:

We know the volume of a cylinder, V = πr²h where r = radius of cylinder and h = height of cylinder.

Now, to find the rate of change of volume, we differentiate it with respect to time. So

dV/dt = d(πr²h)/dt

= πhdr²/dr × dr/dt + πr²dh/dh × dh/dt

= 2πrh × dr/dt + πr² × dh/dt

when r = 17 in, dr/dt = rate of change of radius = + 7 in/s, h = 5 in and dh/dt = rate of change of height = - 3in/s (negative since it is decreasing).

So, dV/dt = 2πrh × dr/dt + πr² × dh/dt

= 2π × 17 in × 5 in × (+ 7 in/s) + π(17 in)² × (- 3 in/s)

= 1190π - 867π

= 323π in³/s

= 1014.73 in³/s

step-by-step explanation:

let's assume

number of candles set =x

price of of x candles =p(x)

we are given

a candle maker prices one set of scented candles at $10 and sells an average of 200 sets each week

so, we get point as (200,10)

he finds that when he reduces the price by $1, he then sells 50 more candle sets each week

so, we can find slope

now, we can use point slope form of line

now, we can plug values

we can use point

and find b

now, we can plug it back

and we get

now, we can find revenue

we know that

revenue = price*quantity

so, we get