Dau 16 puncte ajutati-ma doar 2 ex 5 si 7!!!

5.
a)
7×8+6×7-3×7=
56+6×7-3×7=
56+42-3×7=
56+42-21=
98-21=
=77
9+5×6-25:5=
9+30-25:5=
9+30-5=
39-5=
=34
b)
7×6-12+7×10=
42-12+7×10=
42-12+70=
30+70=
=100
15-15:3+2×5×5=
15-5+2×5×5=
15-5+10×5=
15-5+50=
10+50=
=60
c)
400+4×8+72:9-48=
400+32+72:9-48=
400+32+8-48=
432+8-48=
424-48=
386
300-64:8+6×6-28=
300-8+6×6-28=
300-8+36-28=
292+36-28=
328-28=
=300