Question

12+30 4:4+8:2 10 21x 32x21-31x21 -499 +10

88+8 7+3 2+1

12+3 4:4+8:2 9+5

88-8 7+3 2-1

Answer 1

12+30=42. ,4:4+8:2=1+4=5. ,21×32×21-31×21-499+10=672×21-651-509=14112-142=13970. ,88+8=96. ,7+3=10, 2+1=3. ,12+3=15, 9+5=14,88-8=80;2-1=1