Question

I attached the photo below. I just need part b answered.

Answer 1

`\begin{gathered} Points \\ (2.5,1)(5,2)(7.5,2)(7.5,3)(7.5,4)(10,5)(10,6)(12.5,6) \\ (15,7)(15,8)(17.5,5)(17.5,7)(20,9)(22.5,7)(22.5,9)(25,11) \\ y=ax+b \\ a=(n\Sigma xy-\Sigma x\Sigma y)/(n\Sigma x^2-(\Sigma x)^2) \\ b=(\Sigma y-a\Sigma x)/(n) \\ n=16 \\ \Sigma xy=1515 \\ \Sigma x\Sigma y=(217.5)(92)=20010 \\ \Sigma x^2=3656.25 \\ (\Sigma x)^2=(217.5)^2=47306.25 \\ a=((16)(1515)-20010)/((16)(3656.25)-47306.25) \\ a=0.38 \\ b=((92)-(0.38)(217.5))/(16) \\ b=0.58 \\ Hence \\ The\text{ linear equation is y=0.38x+0.58} \end{gathered}`