To 15 lts of water containing 20% alcohol, we add 5 lts of pure water. What is % alcohol.  Pick:
A) 25%
B) 35%
C) 15%
D) 18%
E) 19%
since 20% alcohol in 15 lit=(15*20)/100= 
<gadget id="calculator">(15*20)/100</gadget>
<output>3</output>
3 lit   since total water=(15-3)+5= 
<gadget id="calculator">(15-3)+5</gadget>
<output>17</output>
17   total mix=3+17= 
<gadget id="calculator">3+17</gadget>
<output>20</output>
20   % of alcohol=(3/20)*100= 
<gadget id="calculator">(3/20)*100</gadget>
<output>15</output>
15%   ANSWER:15%
<result>C</result>
To 15 lts of water containing 20% alcohol, we add 5 lts of pure water. What is % alcohol.