To find the ratio of the number of students who passed the test to the total number of students who took the test, we need to calculate the total number of students first.
The total number of students = number of students who passed + number of students who did not pass = 32 + 16 = 48.
Now, the ratio of the number of students who passed (32) to the total number of students (48) is:
\[ \text{Ratio} = \frac{32}{48}. \]
To simplify this ratio, we divide both the numerator and the denominator by their greatest common divisor, which is 16:
\[ \frac{32 \div 16}{48 \div 16} = \frac{2}{3}. \]
Therefore, the ratio of the number of students who passed the test to the total number of students who took the test is 2/3.