X can finish a work in 15 days. Y can finish the same work in 20 days. Y worked for 12 days and left the job. how many days does X alone need to finish the remaining work?  Choose the most appropriate option:	A) 5	B) 3	C) 4	D) 7	E) 8
Work done by X in 1 day = 1/15   Work done by Y in 1 day = 1/20   Work done by Y in 12 days = 12/20 = 3/5   Remaining work = 1 – 3/5 = 2/5   Number of days in which X can finish the remaining work = (1/3) / (1/15)= 
<gadget id="calculator">(1/3) / (1/15)</gadget>
<output>5</output>
5   5
<result>A</result>
X can finish a work in 15 days. Y can finish the same work in 20 days. Y worked for 12 days and left the job. how many days does X alone need to finish the remaining work?