12 welders work at a constant rate they complete an order in 8 days. If after the first day, 9 welders start to work on the other project, how many more days the remaining welders will need to complete the rest of the order?
Pick:
A) 5  B) 12  C) 18  D) 24  E) 28
1. We need to find out the time taken by 3 workers after day 1.   2. total no.of wokers * total time taken = time taken by 1 worker   3. Time taken by 1 worker = 12*8= 
<gadget id="calculator">12*8</gadget>
<output>96</output>
96 days   4. But on day 1 twelve workers had already worked finishing 1/8 of the job. So 3 workers have to finish only 7/8 of the job.   5. Total time taken by 3 workers can be got from formula used at (2). i.e., 3* total time taken= 96. Total time taken by 3 workers to finish the complete job is 96/3= 
<gadget id="calculator">96/3</gadget>
<output>32</output>
32 days.   6. Time taken by 6 workers to finish 7/8 of the job is 7/8 * 32= 
<gadget id="calculator">7/8 * 32</gadget>
<output>28</output>
28 days.   The answer is choice 28
<result>E</result>
12 welders work at a constant rate they complete an order in 8 days. If after the first day, 9 welders start to work on the other project, how many more days the remaining welders will need to complete the rest of the order?