Question

помогите решить задания

Answer 1

168+23+32+177=(168+32)+(177+23)=200+200=400
15•9•2=(15•2)•9=30•9=270
145•21=3045

Answer 2

1)124*13=1612
2)1612-968=644
3)728:52=14
4)644+14=658
5)8554:658=13
6)13+87=100
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a) 168+23+32+177=(168+32)+(23+177)=200+200=400
б)15*9*2=(15*2)*9=30*9=270
в)145*21=(145*20)+(145*1)=2900+145=(2900+100)+45=3000+45=3045