Question

The total amount of construction spending on highways and streets (in billions of dollars) is given in the accompanying table for the first six months of 2016. Month Spending January 99 February 97 March 93 April 93 May 88 June 85 (a) Find the least-squares regression line that models these data, with x = 1 corresponding to January 2016. (b) Assuming the trend continues, estimate the amount of spending in November 2016. (a) The linear model for the data is y= (x+ (O). (Round to the nearest thousandth as needed.)

Answer 1

i am using minitab to solve the problem.

steps:-

copy the data in minitab (in month type 1 in place of january , 2 in place of february...and so on ) $1596129413881_blob.png$stat $1596129413881_blob.png$ regression $1596129413890_blob.png$ regression $1596129413973_blob.png$ fit regression model $1596129413999_blob.png$ in responses select spending ,in continuous predictors select month $1596129414115_blob.png$ ok$1596129414079_blob.png$ok.

*** SOLUTION ***

a).the linear model for the data is:-

$\mathbf{y=-2.771x+102.200}$

[ where, x = month, y = spending ]

b).for november, x = 11 [ as this is the 11 th month ]

the estimated amount of spending in november 2016 is :-

$=(-2.771*11)+102.200$

$\approx \mathbf{71.72}$

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