Question

DAU COROANA URGENT Efectuati oral urmatoarele adunari, folosind, eventual, proprietatile de asociativitate si comutativitate ale adunarii numerelor intregi: a) (99) + (+102) + (+1) + (-2)
b) (-1 999) + (+7) + (+1 995) - (-0)
c) (+304) + (-4) + (-299) + (-1) + 0
d) 2 001+(32+(42)+(32)+(42)+(-1)

Answer 1

a) (99) + (+102) + (+1) + (-2) = 99+102+1-2 = 202-2 = 200
b) (-1 999) + (+7) + (+1 995) - (-0) =-1 999 +7+ 1995 +0 = 3
c) (+304) + (-4) + (-299) + (-1) + 0 = 304-4-299 -1+0 = 304-304=0
d) 2 001+(32+(42)+(32)+(42)+(-1)= 2 001 +31+42+32+42-1= 2 149 -1 = 2 148

Answer 2

a) (99+1)+(102-2)=200
b) (1995+7-1999) + 0=3
c) (304-299) - (4+1)=5 - 5=0
d) (2001+ 32+32+42+42) - 1=2001 + 64 +84 - 1=2148