An item is regularly priced at $30. It is on sale for 20% off the regular price. How much in dollars) is discounted from the regular price?
Answer:
D
Step-by-step explanation:
i just know i guess
Answer:
5in by 5in by 5in
Step-by-step explanation:
We are not told wat to find but we can as well find the dimension of the prism that will minimize its surface area.
Given
Volume = 125in³
Formula
V = w²h ..... 1
S = 2w²+4wh ..... 2
w is the side length of the square base
h is the height of the prism
125 = w²h
h = 125/w² ..... 3
Substitute eqn 3 into 2 as shown
S = 2w²+4wh
S = 2w²+4w(125/w²)
S = 2w²+500/w
To minimize the surface area, dS/dw = 0
dS/dw =4w-500/w²
0= 4w-500/w²
Multiply through by w²
0 = 4w³-500
-4w³ = -500
w³ = 500/4
w³ =125
w = cuberoot(125)
w = 5in
Get the height
125 =w²h
125 = 25h
h = 125/25
h = 5in
Hence the dimension of the prism is 5in by 5in by 5in
