3 cooks have to make 80 burgers.They are known to make 20 pieces every minute working together.The 1st cook began workin alone and made 20 pieces having worked for sometime more than 3 mins.The remaining part of the work was done by second and 3rd cook working together.It took a total of 8 minutes to complete the 80 burgers.How many minutes would it take the 1st cook alone to cook 160 burgers?	Select.
A) 16 minutes
B) 24 mins
C) 32 mins
D) 40 mins
E) 30 mins
Denote by A, B, C the rates of the three cooks in units of burgers/minute.   A + B + C = 20.   Let t be the time in minutes it took the first cook A to make the 20 burgers. So, A*t = 20, and we know that t &gt; 3.   We need to find 8t, as 160 burgers will be made by A in 8 times more than making 20 burgers.   We already know that 8t &gt;  8*3= 
<gadget id="calculator"> 8*3</gadget>
<output>24</output>
24, so we can eliminate answers (A) and (B).   In addition, (B + C)(8 - t)= 60, or (20 - A)(8 - t) = 60.   Since 20 - A &lt; 20 and 8 - t &lt; 5, looking for integer solutions, we find the only acceptable solution 20 - A = 15 and 8 - t = 4, so t = 4.   I am assuming integer numbers for the solutions based on the answer choices.   Anyway, testing the answer choices, only (C) is a solution.   Therefore, A will make 160 burgers in 8*4= 
<gadget id="calculator">8*4</gadget>
<output>32</output>
32 minutes.   Answer 32 mins
<result>C</result>
3 cooks have to make 80 burgers.They are known to make 20 pieces every minute working together.The 1st cook began workin alone and made 20 pieces having worked for sometime more than 3 mins.The remaining part of the work was done by second and 3rd cook working together.It took a total of 8 minutes to complete the 80 burgers.How many minutes would it take the 1st cook alone to cook 160 burgers?