A rectangular plot measuring 90 metres by 50 metres is to be enclosed by wire fencing. If the poles of the fence are kept 20 metres apart, how many poles will be needed ?  Choose the correct choice.
A) 55 B) 56 C) 14 D) 58 E) None of these
Solution   Perimeter of the plot = 2(90 + 50) = 280 m.   ∴ Number of poles = [280/20= 
<gadget id="calculator">280/20</gadget>
<output>14</output>
14m Answer 14
<result>C</result>
A rectangular plot measuring 90 metres by 50 metres is to be enclosed by wire fencing. If the poles of the fence are kept 20 metres apart, how many poles will be needed ?