This set of values is impossible.
Work Step by Step
1. Is the atomic number equal to the number of protons? - Yes, they are equal. (15) 2. Is the sum of the number of protons and neutrons equal to the mass number? Sum: $15 + 15 = 30$ Mass number: 32 - No, they aren't equal. ($30 \ne 32$) - Therefore, these values aren't possible.