Answer and explanation:
Given : The demand for a product for the last six years has been 15, 15, 17, 18, 20, and 19. The manager wants to predict the demand for this time series using the following simple linear trend equation : 
To find : What are the forecast errors for the 5th and 6th years?
Solution :
Data : 15, 15, 17, 18, 20, and 19.
The simple linear trend equation is given as, 
For t = 5 years



Observed 
Predicted 
Forecast error = Observed – Predicted = 20 – 22 = -2
Absolute forecast error = |-2| = 2
.
For t = 6 years



Observed 
Predicted 
Forecast error = Observed – Predicted = 19 – 24 = -5
Absolute forecast error = |-5| = 5.
Answer:
The actual length of the helicopter is <u>23 feet</u>.
Step-by-step explanation:
Given:
On a scale drawing, a helicopter is 2.3 feet long.
The scale on the drawing shows a ratio of 1 foot to 10 feet.
Now, to find the actual length of the helicopter.
Let the actual length of helicopter be
.
On scale drawing length of helicopter = 2.3 feet.
The scale on the drawing shows a ratio = 1:10.
Now, as ratios are given so by setting proportion we solve it:

<em>By cross multiplying we get:</em>
⇒ 
⇒ 
⇒ 
Therefore, the actual length of the helicopter is 23 feet.
Answer:
0.03 feet
Step-by-step explanation:
d = 0.03r² + r
When d = 0: 0.03r² + r = 0
r(0.03r + 1) = 0
∴ r = 0
When r = 0: d = 0.03 feet
Answer;
a
Step-by-step explanation: