11 runners took at least 30 minutes to finish the race. (:
Answer: The answer is 5. The denominator.
Step-by-step explanation:
I'm just going to write out the answers.
1. 3/6 < 1
2. 5/4 > 1
3. 8/10 < 1
4. 5/8 < 1
5. 7/9 < 1
6. 9/10 < 1
7. 5/8 < 1
8. 11/8 > 1
9. 32/35 < 1
10. 33/36 < 1
11. 13/15 < 1
12. 45/54 < 1
13. 11/10 > 1
14. 52/46 > 1
15. 19/21 < 1
16. 78/80 < 1
Hope this helps! :)
Answer:
<u><em>y = -190 cos(π t / 120) + 195</em></u>
Step-by-step explanation:
<em>General form of a sinusoidal function: y = A cos(Bt - C) + D
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<em>Now generally a cosine function starts at the maximum value, so to start at the minimum value, flip the cosine function by making it negative.
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<em>A is the amplitude of the curve and will be the radius of the ferris wheel. Therefore, A = 380 / 2 = 190 feet.
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2π / B is the period of the curve and will be the time to complete one full rotation. The time to complete one full rotation is given as 4 minutes. Convert this into seconds to get period = 4 minutes * (60 seconds / minute) = 240 seconds. Therefore, B = 2π / period = 2π / 240 seconds = π / 120.
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C/B is the phase shift, or horizontal shift of the graph. Since the negative cosine function already starts at the minimum value, there is no phase shift so C/B = 0, meaning C = 0.
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D is the vertical shift and will be the height of the center of the ferris wheel. Therefore, D = 195 feet.
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Your final function will be:</em>
<u><em>y = -190 cos(π t / 120) + 195</em></u>
Answer:
Step-by-step explanation:
We have the equations
4x + 3y = 18 where x = the side of the square and y = the side of the triangle
For the areas:
A = x^2 + √3y/2* y/2
A = x^2 + √3y^2/4
From the first equation x = (18 - 3y)/4
So substituting in the area equation:
A = [ (18 - 3y)/4]^2 + √3y^2/4
A = (18 - 3y)^2 / 16 + √3y^2/4
Now for maximum / minimum area the derivative = 0 so we have
A' = 1/16 * 2(18 - 3y) * -3 + 1/4 * 2√3 y = 0
-3/8 (18 - 3y) + √3 y /2 = 0
-27/4 + 9y/8 + √3y /2 = 0
-54 + 9y + 4√3y = 0
y = 54 / 15.93
= 3.39 metres
So x = (18-3(3.39) / 4 = 1.96.
This is a minimum value for x.
So the total length of wire the square for minimum total area is 4 * 1.96
= 7.84 m
There is no maximum area as the equation for the total area is a quadratic with a positive leading coefficient.
