A and B can together finish a work in 40days. They worked together for 10days and then B left. After another 9days, A finished the remaining work. In how many days A alone can finish the job?
Choose the correct answer:	A) 12	B) 25	C) 60	D) 30	E) 20
12+B 10days work = 10*1/40 = 1/4   Remaining work = 1-1/4 = 3/4   3/4 work is done by 12 in 9 days   whole work will be done by 12 in  9*4/3= 
<gadget id="calculator"> 9*4/3</gadget>
<output>12</output>
12 days   12nswer is 12
<result>A</result>
A and B can together finish a work in 40days. They worked together for 10days and then B left. After another 9days, A finished the remaining work. In how many days A alone can finish the job?