X= {1.04, 1.34, 1.4, 1.53, 1.66, 1.72, 2.02, 2.12, 2.2}
y= {30, 35, 40, 45, 50, 55, 60, 65, 70}
find the slob (m) ?

Slope between points for points (x1,y1) and (x2,y2) is (y2-y1)/(x2-x1)

pick any 2

(1.04,30) and (1.34,35)
slope=(35-30)/(1.34-1.04)=5/0.3=50/3

slope=50/3
however, that is not the slope for all points

we can try to get the closest average by taking slope between first and last point

(1.04,30) and (2.2,70)

slope=(70-30)/(2.2-1.04)=40/1.16=1000/29
the average slope might be 1000/29