13× (a)   =78

12× (a)   =84

50×20= (a)  

96÷4= (a)  

(a)   ÷ 6=9

108÷ 4= (a)  

5000÷100= (a)  

100×200= (a)  

420- 215= (a)  

328+222= (a)  

450÷15= (a)  

81÷3= (a)  

25+25+25+25+50+15+45= (a)  

20× (a)   =180

11×0×4= (a)  

65÷ (a)   =13

13×13= (a)  

19×19= (a)  

245÷5= (a)  

231÷3= (a)  

23×6= (a)  

2560- (a)   =240