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>
Median: 29
Range: 25
IQR: 14.5
Explanations:
**Median:**
(To find the median, we need to first order all the elements)
Ordered —> 15, 18, 18, 20, 23, 28, 30, 33, 33, 34, 38, 40
(Since there are an even number of elements, we need to add the two elements in the middle and divide by 2)
Median = (28 + 30)/2 = 58/2 = 29
**Range:**
(To find the range, you just have the subtract the smallest one from the largest)
Range = 40 - 15 = 25
**IQR:**
First half of elements —> 15, 18, 18, 20, 23, 28
Second half of elements —> 30, 33, 33, 34, 38, 40
Q1 (Quartile 1) = Median of first half = (18 + 20)/2 = 38/2 = 19
Q3 (Quartile 3) = Median of second half = (33 + 34)/2 = 67/2 = 33.5
IQR = Q3 - Q1 = 33.5 - 19 = 14.5
A20-a18=a1+19d-a1-17d=2d =281-97
so
d=92
Answer:
-1
Step-by-step explanation:
-3(2) = -6 + 5 = -1