Write an equation of the trend line, rounding to two decimal places as needed. For this problem, choose the points (1990,255) and (2002,321). Choose the correct answer below.

A. y = -5.5x - 587.5

B. y = 5.5x + 587.5

C. y = -5.5x + 10,690

D. y = 5.5x - 10,690

3 answers

To find the equation of the trend line, we can use the equation of a line:

y = mx + b

where m is the slope and b is the y-intercept.

First, let's find the slope. The slope (m) is given by:

m = (y2 - y1) / (x2 - x1)

Using the points (1990, 255) and (2002, 321), we have:

m = (321 - 255) / (2002 - 1990)
m = 66 / 12
m = 5.5

Now, we can find the y-intercept by substituting the slope (m) and one of the points into the equation:

255 = 5.5(1990) + b
255 = 10,945 + b

To solve for b, we subtract 10,945 from both sides:

255 - 10,945 = b
b = -10,690

Therefore, the equation of the trend line is:

y = 5.5x - 10,690

The correct answer is D. y = 5.5x - 10,690.
Estimate the attendance at theme parks in the country in 2005.
The estimated attendance was [ ]million.
​(Round to the nearest whole number as needed. Use the answer from the previous part to find this​ answer.)
To estimate the attendance at theme parks in the country in 2005, we can use the equation of the trend line and substitute x=2005 into it.

The equation of the trend line is:

y = 5.5x - 10,690

Substituting x=2005 into the equation, we have:

y = 5.5(2005) - 10,690
y = 11,027.5 - 10,690
y ≈ 337.5

Rounding to the nearest whole number, the estimated attendance at theme parks in the country in 2005 is 338 million.

Therefore, the answer is 338.