A CAN FINISH A WORK IN 21 DAYS AND B CAN DO THE SAME WORK IN15 DAYS. B WORKED FOR 10 DAYS AND LEFT THE JOB. IN HOW MANY DAYS, A ALONE CAN FINISH THE REMAINING WORK?
Choose the most appropriate option.
A) 5	B) 5 1/2	C) 7	D) 8	E) NONE OF THESE
B'S 10 DAY'S WORK=(1/15*10)=2/3 REMAINING WORK = (1-2/3)=1/3   NOW, 1/18 WORK IS DONE BY A IN 1 DAY   1/3 WORK IS DONE BY A IN  (21*1/3)= 
<gadget id="calculator"> (21*1/3)</gadget>
<output>7</output>
7 DAYS.   7ORRE7T OPTION:7
<result>C</result>
A CAN FINISH A WORK IN 21 DAYS AND B CAN DO THE SAME WORK IN15 DAYS. B WORKED FOR 10 DAYS AND LEFT THE JOB. IN HOW MANY DAYS, A ALONE CAN FINISH THE REMAINING WORK?