In one alloy there is 12% chromium while in another alloy it is 8%. 15 kg of the first alloy was melted together with 40 kg of the second one to form a third alloy. Find the percentage of chromium in the new alloy.  Choices.
A) 8.8% B) 9% C) 9.2% D) 9.1% E) 8.4%
The amount of chromium in the new 15+40= 
<gadget id="calculator">15+40</gadget>
<output>55</output>
55 kg alloy is  0.12*15+0.08*40= 
<gadget id="calculator"> 0.12*15+0.08*40</gadget>
<output>5</output>
5 kg, so the percentage is 5/55*100=9.1%.   Answer: 9.1%.
<result>D</result>
In one alloy there is 12% chromium while in another alloy it is 8%. 15 kg of the first alloy was melted together with 40 kg of the second one to form a third alloy. Find the percentage of chromium in the new alloy.