how many liters of pure alcohol must be added to a 100 - liter solution that is 20 percent alcohol in order to produce a solution that is 35 percent alcohol ?
"20 % alcohol solution means ; in the 100 liter solution , 20 liters of solution is alcohol and 80 liters other solvents . if we addxliters of alcohol to the solution , the solution becomes 100 + xliters and alcohol , which was 20 liters , becomes 20 + x liters . according to the statement ; 20 + x = 35 % of ( 100 + x ) or 20 + x = ( 100 + x ) 7 / 20 400 + 20 x = 700 + 7 x 13 x = 300 x = 300 / 13 ans : b"
divide(100, add(const_4, const_3))