9 men and 12 boys finish a job in 12 days, 12 men and 12 boys finish it in 10 days. 10 men and 10 boys shall finish it in how many days?	Choose the correct answer.
A) 12
B) 10
C) 8
D) 5
E) 6
9M + 12B ----- 12 days   12M + 12B ------- 10 days   10M + 10B -------?   108M + 144B = 120M +120B   24B = 12M =&gt; 1M = 2B   18B + 12B = 30B ---- 12 days   20B + 10B  18  + 12= 
<gadget id="calculator"> 18  + 12</gadget>
<output>30</output>
30B ---- 12 days   20B + 10B = 30B -----?   20  + 10= 
<gadget id="calculator">  20  + 10</gadget>
<output>30</output>
30B -----?=&gt; 12 days   12NSWER 12
<result>A</result>
9 men and 12 boys finish a job in 12 days, 12 men and 12 boys finish it in 10 days. 10 men and 10 boys shall finish it in how many days?