A farmer collected data on the annual rainfall, x cm, and the annual yield of peas, p tonnes per acre - Edexcel - A-Level Maths Statistics - Question 4 - 2011 - Paper 1
Question 4
A farmer collected data on the annual rainfall, x cm, and the annual yield of peas, p tonnes per acre.
The data for annual rainfall was coded using v = \frac{x-5}{1... show full transcript
Worked Solution & Example Answer:A farmer collected data on the annual rainfall, x cm, and the annual yield of peas, p tonnes per acre - Edexcel - A-Level Maths Statistics - Question 4 - 2011 - Paper 1
Step 1
Find the equation of the regression line of p on v in the form p = a + bv
96%
114 rated
Only available for registered users.
Sign up now to view full answer, or log in if you already have an account!
Answer
To find the regression line, we use the formula:
The gradient (b) is given by:
b=SwSpm=5.7531.688≈0.293
The intercept (a) can be calculated as:
a=pˉ−b⋅vˉ=1.168−0.293⋅4.42≈1.168−1.293=−0.125
Thus, the equation of the regression line is:
p=−0.125+0.293v
Step 2
Using your regression line estimate the annual yield of peas per acre when the annual rainfall is 85 cm
99%
104 rated
Only available for registered users.
Sign up now to view full answer, or log in if you already have an account!
Answer
First, we need to calculate the value of v when x = 85 cm:
v=1085−5=1080=8
Using the regression equation: p=−0.125+0.293⋅8≈−0.125+2.344=2.219
Therefore, the estimated annual yield of peas per acre is approximately 2.219 tonnes.