This is the concept of linear scale factor:
The length of the farmer shadow will be calculated as follows:
(height of farmer)/(length of farmer shadow)=(height of the silo)/(length of silo shadow)
let the length of farmer shadow be x
height of farmer=72 inches= 6 ft
length of silo shadow=31.5 ft
height of silo=140 ft
therefore plugging the above in the equation we get:
6/x=140/31.5
solving for x we get
x/6=31.5/140
x=31.5/140×6
x=1.35 ft
The length of the farmer shadow is 1.35 ft
