Question

A Math 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 1

The answer is 80%:

Step 1:42%-15%=17%
Step 2: 100%-17%=80%
Step 3: This means that 80% of the class passed the first and second test

Answer 2

42%-25%=17%

Explanation:

100%-17%=67%

67%passed both first and second test