3. (8 points) Red gift boxes cost 5 yuan each, containing 3 spinning tops; yellow gift boxes cost 9 yuan each, containing 5 spinning tops. Lei Lei spent 600 yuan to buy 72 gift boxes, and these gift boxes can be opened to get $\qquad$ spinning tops.
【Solution】Solution: According to the problem, we have:
Assume all are yellow gift boxes. It would require $72 \times 9=648$ yuan.
Therefore, the number of red gift boxes is $(648-600) \div(9-5)=12$ (boxes);
Thus, the total number of spinning tops is $3 \times 12+(72-12) \times 5=336$ (tops);
Hence, the answer is: 336