Assuming that a person of normal sight can read print to such distance that the letters subtend an angle of 5’ at his eye, find the height of the letters that he can read at a distance of 12 metres.

Explanation

Convert `5'` into degrees


`= 5/ 60` degrees.


Now replace it in the equation `tan (5/60) = (PQ)/(12)`


` PQ = 12 * tan (1/12)`


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