After a mathematics exam, 20 percent of the students reported that they didn't study, while 20 percent of the students who didn't study refused to admit they hadn't studied. What percent of the students didn't study? Choose one:
A) 15% B) 50% C) 35% D) 20% E) 25%
Statement: 20% of Students (S) Reported they Didn't Study (RDS). Of the students who didn't study (DS) 20% refused to admit they didn't study (notRDT). [Note: A Venn Diagram is useful to visualize the problem.]   Solution: Sample space is 100%.   S = 100%   RDS/S = 20%   notRDS/DS = 20% =&gt; 100% - 20% =&gt; RDS/DS = 80%   DS/S = (20)/(80)% = 25%   Answer: 25%
<result>E</result>
After a mathematics exam, 20 percent of the students reported that they didn't study, while 20 percent of the students who didn't study refused to admit they hadn't studied. What percent of the students didn't study?