共30题用时5分钟

50-28=

38+36=

58+16=

80-34=

28+27=

56-38=

28+39=

9+18-6=

38-9=

34+38=

18+9-16=

37-18=

62-38=

13+15-19=

80-34=

51-18=

12+6-15=

76-54=

35+26=

12+6-18=

82-37=

54-54=

13+8+19=

9+16=

50-26=

30-15-14=

30-16-5=

64-13=

30-19-8=

30-5-17=