5. On the test Katy is taking, \( 4 / 15 \) of the questions are worth 1 point and \( 6 / 15 \) of the questions 2 points. The rest of the questions are worth 3 points. What fraction of the test questions are worth 3 points?

To find the fraction of the test questions that are worth 3 points, we first determine the total fraction of questions accounted for by the 1 point and 2 point questions. The questions worth 1 point make up \( \frac{4}{15} \) of the total, and those worth 2 points make up \( \frac{6}{15} \). Adding these together gives: \[ \frac{4}{15} + \frac{6}{15} = \frac{10}{15}. \] To find the fraction of questions that are worth 3 points, we note that: \[ 1 - \frac{10}{15} = \frac{5}{15}. \] This simplifies to: \[ \frac{1}{3}. \] Thus, the fraction of the test questions that are worth 3 points is \( \frac{1}{3} \).