A man can row upstream at 7 kmph and downstream at 33 kmph, and then find the speed of the man in still water? Select the correct option.
A) 11
B) 77
C) 30
D) 20
E) 34
US = 7   20S = 33   M = (33 + 7)/2= 
<gadget id="calculator">(33 + 7)/2</gadget>
<output>20</output>
20   Answer:20
<result>D</result>
A man can row upstream at 7 kmph and downstream at 33 kmph, and then find the speed of the man in still water?