(13-13÷13)×2=2413×(12-10)-2=2413×2+10-12=24(12+10)÷2+13=24
到底是用几个数算24？用5个数:13+13–2+13–13=2413+13÷13×13–2=2413+13–2×13÷13=24用4个数:（12–10）×13–2=2413×2+10–12=24
