X can finish a work in 36 days. Y can finish the same work in 24 days. Y worked for 12 days and left the job. how many days does X alone need to finish the remaining work? Options:  A) 12  B) 13  C) 16  D) 17  E) 18
Work done by X in 1 day = 1/36   Work done by Y in 1 day = 1/24   Work done by Y in 12 days = 12/24 = 1/2   Remaining work = 1 – 1/2 = 1/2   Number of days in which X can finish the remaining work = (1/2) / (1/36)= 
<gadget id="calculator">(1/2) / (1/36)</gadget>
<output>18</output>
18   18
<result>E</result>
X can finish a work in 36 days. Y can finish the same work in 24 days. Y worked for 12 days and left the job. how many days does X alone need to finish the remaining work?