1、 (10 × 10 - 4) ÷ 4
2、
(2*(13-7))+12
12-(2*(7-13))
12+(2*(13-7))
12-((7-13)*2)
12/(7-(13/2))
12+((13-7)*2)
((13-7)*2)+12
3、
8/(3-(8/3))
4、
(5-(1/5))*5
(5-(1/5))*5
5*(5-(1/5))
5*(5-(1/5))
(5-(1/5))*5
(5-(1/5))*5
5*(5-(1/5))
5*(5-(1/5))
(5-(1/5))*5
(5-(1/5))*5
5*(5-(1/5))
5*(5-(1/5))