A man swims downstream 72 km and upstream 45 km taking 9 hours each time; what is the speed of the current ?  Choose the correct answer:  A) 2.5 kmph  B) 6.5 kmph  C) 1.5 kmph  D) 8.5 kmph  E) 1.7 kmph
Explanation:   72 --- 9   ? ---- 1   =&gt; Down Stream = 8   45 ---- 9   ? ---- 1   =&gt; Up Stream = 5   Speed od current S = ?   S = (8 - 5)/2= 
<gadget id="calculator">(8 - 5)/2</gadget>
<output>3/2 = around 1.5</output>
1.5 kmph.   Answer: 1.5 kmph
<result>C</result>
A man swims downstream 72 km and upstream 45 km taking 9 hours each time; what is the speed of the current ?