The perimiter is 4 times 1 side
currently, it is 9 times 4 or 36
increased by 3
I think y mean times 3
so 9*3=27
new perimiter is 27*4=108
how much larger is it?
108-36=72
it is 72cm larger
it is the first answer
(it isn't cm² because that is for area and we are calculating perimiter)
Answer:
Yes
Step-by-step explanation:
They are proportional by a scale of 1.5
So Volume of cylinder is pi*r^2*h = 1,000
Then lightest one means you have the smallest surface area. Which is one base and then the area of the surface. SA = pi*r^2 + 2pi*r*h
So now you have 2 equations, so:
h = 1,000/(pi*r^2)
So then SA = pi*r^2 + 2pi*r*(1,000/(pi*r^2) = pi*r^2 + 2,000/r
Derivative of SA is then 2pi*r -2,000/r^2. Set to 0
2pi*r-2,000/r^2 =0 --> 2pi*r^3 = 2,000 --> r^3 = 1,000/pi --> r = 10/pi^(1/3)
Now go back to the volume function: pi*r^2*h =1,000 --> 1,000/(pi*100/pi^(2/3)) = h
<span>h = 10 / pi^(1/3)</span>
