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$$11-4=7$$  

$$4+7=11$$  

$$7+4=11$$  

$$7-4=3$$  

$$24-5=19$$  

$$5+24=29$$  

$$29-5=24$$  

$$29-24=5$$  

$$199-100=99$$  

$$99+100=199$$  

$$100-99=1$$  

$$100+99=199$$  

$$80-30=50$$  

$$80-40=40$$  

$$8-5=3$$  

$$50+30=80$$  

$$65+345=410$$  

$$410-65=345$$  

$$410-345=65$$  

$$345+41=650$$  

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Multiplication

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Subtraction

$$5+5=10$$  

$$10+5=15$$  

$$5-5=0$$  

$$10-5=5$$  

$$15-p=3$$  

$$15+3=18$$  

$$3+15=18$$  

$$15-3=p$$  

$$46-21=25$$  

$$46-25=21$$  

$$46+21=67$$  

$$67-21=46$$  

$$20+14=34$$  

$$14+t=20$$  

$$t+14=20$$  

$$14+14=28$$  

$$33-3=30$$  

$$33-30=3$$  

$$30+3=33$$  

$$30-3=27$$  

$$450+27=477$$  

$$450+423=873$$  

$$423+27=450$$  

$$27+423=450$$  

$$2000-1236=764$$  

$$2000+764=2764$$  

$$1236+764=2000$$  

$$2000+1236=3236$$  

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Addition

Multiplication

Division

Subtraction

Multiplication

Division

$$32-15=17$$  

$$32+15=47$$  

$$47-32=15$$  

$$17-15=2$$  

$$780-50=730$$  

$$730+50=780$$  

$$680-50=630$$  

$$680+50=730$$