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Which does not belong?

• 14+3=17

• 17-14=3

• 1+17=14

• 17-3=14

Which does not belong?

• 11+2=9

• 9+2=11

• 11-9=2

• 2+9=11

Which does not belong?

• 25+5=30

• 30-5=25

• 5+25=30

• 25-5=30

Which one doesn't belong?

• 40+50=90

• 90-50=40

• 50-40=90

• 50+40=90

Which one doesn't belong?

• 60-3=63

• 63-3=60

• 3+60=63

• 60+3=63

Choose: Start Unknown

• 42-x=13

• x+14=25

• 38+4=x

Choose comparing:

• 9+5=14

• 24+3=27

• 19-2=17

Choose start unknown:

• 18+3=x

• 25-x=14

• x+36=64

Choose result unknown:

• 14-6=x

• 25+x=38

• x-17=35

Choose change unknown:

• 81-5=x

• x+32=71

• 54-x=22