12÷(5分之3+3分之2)=?
=12÷(9/15+10/15)
=12×15/19
=180/19;
12÷【5分之3×（3分之4-1）】=?
=12÷(3/5×(1/3))
=12÷(1/5)
=60;
很高興為您解答,skyhunter002為您答疑解惑
如果本題有什么不明白可以追問,