Some of 50%-intensity red paint is replaced with 25% solution of red paint such that the new paint intensity is 30%. What fraction of the original paint was replaced? Choose the correct choice from the following choices:
A) 1/30
B) 1/5
C) 2/3
D) 3/4
E) 4/5
Let total paint = 1   Let amount replaced = x   50 (1-x) + 25x = 30   x = 4/5   ANSW4/5R:4/5
<result>E</result>
Some of 50%-intensity red paint is replaced with 25% solution of red paint such that the new paint intensity is 30%. What fraction of the original paint was replaced?