Q32 of 27 Page 1

If the angles of elevation of the top of the candle from two coins distant ‘a’ cm and ‘b’ cm (a>b) from its base and in the same straight line from it are 30° and 60°, then find the height of the candle.



Let AB=candle


C and D are coins


tan60°= AB/BC = h/b


√3 = h/b


h = b√3 --------------(1)


tan30°= AB/BD = h/a


1/√3 = h/a


h = a/√3 --------------(2)


Multiplying (1) and (2), we get


h2= b√3 × a/√3


h2 = ba


h =√ab m


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