A rectangular plot measuring 90 metres by 40 metres is to be enclosed by wire fencing. If the poles of the fence are kept 5 metres apart, how many poles will be needed ?  Choose the correct choice from the following choices:
A) 55	B) 56	C) 57	D) 52	E) None of these
Solution   Perimeter of the plot = 2(90 + 40) = 260 m.   ∴ Number of poles = [260/5= 
<gadget id="calculator">260/5</gadget>
<output>52</output>
52m   Answer 52
<result>D</result>
A rectangular plot measuring 90 metres by 40 metres is to be enclosed by wire fencing. If the poles of the fence are kept 5 metres apart, how many poles will be needed ?