12. (3 points) The school organized a spring outing, renting boats for students to row. If each boat seats 3 people, 16 people are left without a boat; if each boat seats 5 people, one boat is short of 4 people. The school has a total of $\qquad$ students.
【Answer】Solution: Boats: $(16+4) \div(5-3)$, $=20 \div 2$,
$=10$ (boats);
Students: $3 \times 10+16=46$ (people);
Answer: The school has a total of 46 students.