In addition to spanning a river which is 50 metres wide, a straight bridge also has considerable overlap of both banks of the river. One third of the bridge overlaps one bank and one half overlaps the other bank. The total length,in metres, of this bridge is

A. 100
B.150
C.200
D.300
E.400

1 answer

1/2 + 1/3 = 5/6

so, only 1/6 of the bridge is over water.

x/6 = 50
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