Worker A takes 8 hours to do a job. Worker B takes 10 hours to do the same job. How long it take both A & B, working together but independently, to do the same job?	Choose the correct choice from the following choices.
A) 20/9  B) 40/9  C) 50/9  D) 60/9  E) 80/9
one day work of A = 1/8   one day work of 40/9 = 1/10   so one day work of A and 40/9 together = 1/8 + 1/10 = 9/40   so total days required = 40/9   ANSWER:40/9
<result>B</result>
Worker A takes 8 hours to do a job. Worker B takes 10 hours to do the same job. How long it take both A & B, working together but independently, to do the same job?