If 12 men or 20 women can do a piece of work in 54 days, then in how many days can 9 men and 21 women together do the work?  Select the correct option:	A) 10 days	B) 30 days	C) 20 days	D) 80 days	E) 40 days
B 30 days   Given that 12m = 20w =&gt; 3m = 5w   9 men + 21 women = 15 women + 21 women = 36 women   20 women can do the work in 54 days. So, 36 women can do it in   (20 * 54) /36= 
<gadget id="calculator">  (20 * 54) /36</gadget>
<output>30</output>
30 days.
<result>B</result>
If 12 men or 20 women can do a piece of work in 54 days, then in how many days can 9 men and 21 women together do the work?