SOLUTION: A mathematics teacher gave her class two tests. 25% of the class passed both tests and 42% of the class passed the first test. What percent of those who passed the first test also

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Question 1179913: A mathematics teacher gave her class two tests. 25% of the class passed both tests and 42% of the class passed the first test. What percent of those who passed the first test also passed the second test?
Answer by ikleyn(52797) About Me  (Show Source):
You can put this solution on YOUR website!
.

To simplify your thinking, imagine that the class consists of 100 students.


Then the number of those who passed the first test is 42, while the number of those who passed both tests is 25.


The problem asks what percent is 25 of 42.


The answer is  %2825%2F42%29%2A100 = 59.52%  (rounded)    ANSWER

Now it should be CRYSTALLY clear to you.