Its not 70 its 56, because you have to see how many minutes it takes for 1 to do 4 walls which would be 40*8.
Then you have to see if how many minutes its take a person to do one wall which is 8*40/4 from getting the amount of the 1 person doing 4 walls and get 80.
Then you need to see how many walls a person can paint 7 walls out of 10 people.So, we know how many minutes for each wall which is 80 and then multiply it by 7 to get 560 and divide it by 10 to get a product of 56.
Answer:
x = 8,49 ft
y = 4,24 ft
Step-by-step explanation:
Let x be the longer side of rectangle and y the shorter
Area of rectangle = 36 ft² 36 = x* y ⇒ y =36/x
Perimeter of rectangle:
P = 2x + 2y for convinience we will write it as P = ( 2x + y ) + y
C(x,y) = 1 * ( 2x + y ) + 3* y
The cost equation as function of x is:
C(x) = 2x + 36/x + 108/x
C(x) = 2x + 144/x
Taking derivatives on both sides of the equation
C´(x) = 2 - 144/x²
C´(x) = 0 2 - 144/x² = 0 ⇒ 2x² -144 = 0 ⇒ x² = 72
x = 8,49 ft y = 36/8.49 y = 4,24 ft
How can we be sure that value will give us a minimun
We get second derivative
C´(x) = 2 - 144/x² ⇒C´´(x) = 2x (144)/ x⁴
so C´´(x) > 0
condition for a minimum
Answer:
D
Step-by-step explanation:
0.0246909 hope this helps love ❤️
