12) the radius is 15 so with the equation (3.14)*r^2, we get (3.14)(15^2)=706.5
13) true, true (if x=4), true
14) y=0.75x+4.50, $8.25
Answer:
$9327
Step-by-step explanation:
Apparently, the cost function is supposed to be ...
C(x) = 0.4x^2 -112x +17167
This can be rewritten to vertex form as ...
C(x) = 0.4(x^2 -280) +17167
C(x) = 0.4(x -140)^2 +17167 -0.4(19600)
C(x) = 0.4(x -140)^2 +9327
The vertex of the cost function is ...
(x, C(x)) = (140, 9327)
The minimum unit cost is $9327.
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<em>Comment on the question</em>
You found the number of units that result in minimum cost (140 units), but you have to evaluate C(140) to find the minimum unit cost.
You put the highest exponent power first, then you go down until you reach a regular number (a number with a variable goes before a normal number)
Ex: 5x^3+2x^2+4x+5
Answer:
10
Step-by-step explanation:
P(at least 5 rolls until 1) = P(4 rolls are not 1) = 5/6 x 5/6 x 5/6 x 5/6 = 0.4823 (4sf)
Fewer than 7 rolls to get second 1 after first takes 3 rolls means second occurs on 4th, 5th or 6th roll
The probability of each of these is 1/6, 5/6 x 1/6 and 5/6 x 5/6 x 1/6 respectively.
P(second 1 on 4th, 5th or 6th roll) = 1/6 + 5/36 + 25/216 = 91/216 = 0.4213 (4sf)