a hot air ballon was at 2,180 feet. it decended at 120 feet per minute for 9 minutes. what is the balloons new height?
1 answer:
Answer:
The balloons new height is
Step-by-step explanation:
Let
x ----> the number of minutes
y ----> the height of a hot air balloon in feet
we know that
The linear equation in slope intercept form is equal to
where
m is the slope or unit rate
b is the y-intercept or initial value
In this problem we have
The slope is equal to
---> is negative because is a decreasing function
The y-intercept is equal to
substitute
For x=9 minutes
substitute in the linear equation
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Answer:
- The answer or forecast for temperature using a three-day moving average =
- The answer or forecast for temperature using a three-day moving average =
- The mean absolute deviation based on a two-day moving average, covering all days =
Step-by-step explanation:
1. Three-point averages are calculated by taking a number in the series with the previous and next numbers and averaging the three of them.
Step I - Calculate the three series of succession of numbers form the data and find the average of each of them:
A) (90 + 93 +90)/3 = 91.00
B) (93 + 92 + 90)/3 = 91.67
C) (90 + 92 +90)/3 = 90.67
D) (92 + 90 + 88)/3 = 90.00
E) (90 + 88 + 98)/3 = 92.00
So our series approximated to the nearest whole number is:
91, 92, 91, 90, 92
STEP II
From the series above the highest temperature today is unpredictable because the series is irregular. It went from 91 to 92, then it dropped to 90 and came back to 92.
2. Using a two day moving average we have
STEP I .
Calculate the moving averages
A) (90+93)/2 = 91.50
B) (93 + 90)/2 = 91.50
C) (90 + 92)/2 = 91.00
D) (92 +90)/2 = 91.00
E) (90 + 88)/2 = 89.00
F) (88 + 98)/2 = 93.00
STEP II
The temperature also cannot be predicted because of the irregular series.
3. Calculating the Mean Absolute Deviation based on a two-day moving average
The formula for MAD = (∑||)/
STEP I
To find the mean absolute deviation of the data, start by finding the mean of the data set.
Mean of the data set =
(91.50 + 91.50 + 91.00 + 91.00 + 89.00 +93.00)/6
Mean = 91.17
STEP II
Get the distance between the data point and the mean:
- 91.50-91.17=0.33
- 91.50-91.17= 0.33
- 91.00-91.17= -0.17
- 91.00-91.17= -0.17
- 89.00-91.17= -2.17
- 90.00-91.17= -1.17
STEP II
Add all the distances together
0.33 + 0.33 - 0.17 - 0.17 - 2.17 - 1.17 = -3.02
STEP III
Divide the the sum by data points
-3.02/6
= -0.50
So on average the temperatures were <em>-0.50</em> from the mean.
Cheers!
The hole is 8 feet deep at ground level ⇒ 3rd answer
Step-by-step explanation:
The form of the quadratic function is y = ax² + bx + c, where
- a is the coefficient of x²
- b is the coefficient of x
- c is the y-intercept (at x = 0)
The vertex point of the quadratic is (h , k), where
and k is the value of y when x = h
The table:
→ x : -2 , 0 , 2
→ y : -6 , -8 , -6
∵ x represents distance from hole's center in feet
∵ y represents the depth from level ground
∴ The quadratic function is y = ax² + bx + c
∵ c is the value of y at x = 0 ⇒ y-intercept
- From the table at x = 0 ⇒ y = -8
∴ c = -8
- Substitute its value in the function model
∴ y = ax² + bx - 8
- To find the values of a and b substitute x and y in the model by
the coordinates of the point in the table
∵ x = -2 and y = -6
∴ -6 = a(-2)² + b(-2) - 8
∴ -6 = 4a - 2b - 8
- Add 8 to both sides
∴ 2 = 4a - 2b
- Switch the two sides
∴ 4a - 2b = 2 ⇒ (1)
∵ x = 2 and y = -6
∴ -6 = a(2)² + b(2) - 8
∴ -6 = 4a + 2b - 8
- Add 8 to both sides
∴ 2 = 4a + 2b
- Switch the two sides
∴ 4a + 2b = 2 ⇒ (2)
Now we have a system of equation to solve it
Add equations(1) and (2) to eliminate b
∵ 8a = 4
- Divide both sides by 8
∴ a = 0.5
- Substitute value of a in equation (1) or to to find b
∵ 4(0.5) + 2b = 2
∴ 2 + 2b = 2
- Subtract 2 from both sides
∴ 2b = 0
- Divide both sides by 2
∴ b = 0
Substitute the values of a and b in the function model
∴ y = 0.5x² + (0)x - 8
∴ y = 0.5x² - 8
∵ y represents the depth from level ground
∵ The vertex of the function model is (h , k)
∴ The deep of the hole at ground level is the value of k
∵
∴
∴ h = 0
∵ k is the value of y when x = h
- From the table at x = 0 ⇒ y = -8
∴ k = -8
- Ignore the sign (-) because the k represents the depth of the
hole in feet
∴ The deep of the hole at ground level is 8 feet
The hole is 8 feet deep at ground level
Learn more:
You can learn more about the quadratic function in brainly.com/question/1332667
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