Answer:
x = 59.4 ft
y = 84.18ft
Step-by-step explanation:
The cost of exterior walls is $150 per linear foot.
The cost of interior walls is $100 per linear foot.
xy = 5000
y = 5000/x
For the exterior walls, we have 2(x+y)(120)
For the interior wall, we have 100x
The cost function = C
C = 2(x+y)(120) + 100x
C= 240(x+y) + 100x
= 240x + 240y + 100x
= 340x + 240y
Recall that y = 5000/x
C = 340x + 240(5000/x)
C = 340x + 1200000/x
Differentiate C with respect to x
C'(x) = 340 - 1200000/x^2
= (340x^2 -1200000) / x^2
To minimize cost C'(x) = 0
(340x^2 -1200000) / x^2 = 0
340x^2 -1200000 = 0
340x^2 = 1200000
x^2 = 1200000/340
x = √1200000/340
x = 59.4 ft
Recall that y = 5000/x
y = 5000/59.4
y = 84.18 ft
Answer:
y = -5/3 x + 11/3
Step-by-step explanation:
5x +3y = 11
3y = 11 - 5x
y = -5/3 x + 11/3
total length of the boards = 4 1/2 meters
Given:
number of boards = 5
length of each board = 9/10 meters
5 * 9/10 = (5*9)/10 = 45/10
Simplify fraction:
45/10 = 4 5/10 or 4 1/2 meters.
Answer:
(a) Probability that a random sample of n = 45 oil changes results in a sample mean time < 10 minutes i=0.0001.
(b) The mean oil-change time is 15.55 minutes.
Step-by-step explanation:
Let us denote the sample mean time as x
From the Then x = mean time = 16.2 minutes
The given standard deviation = 3.4 minutes
The value of n sample size = 45
CHECK THE ATTACHMENT FOR DETAILED EXPLANATION
Hello there
the answer is−2x=−8x+8
Step 1: Add 8x to both sides.
−2x+8x=−8x+8+8x
6x=8
Step 2: Divide both sides by 6.
6x
6
=
8
6
x=4/3
hope this helps
