When the mercury thread rises to 3/4th of the distance between the two fixed points, what is the temperature indicated by the Fahrenheit scale?

Explanation

Consider the length of mercury thread between the two fixed points as 'l'.
Then, `l=DeltaF=180^(@)F` . . .(1)
Find `(3)/(4)l` by multipying `(3)/(4)` with `180^(@)F` (2)
here, LFP for Fahrenheit scale is `32^(@)F`. So, add `32^(@)F` tot eh answer obtaine din the equation (2).
This becomes the temperature indicated by the fahrenheit scale, when the mercury thread rises to (3/4) th of the distance between its two fixed points.