Răspuns:
1) (4×b+3):47=19rest6
4×b+3=(47-6)×19
4×b+3=41×19
4×b+3=779
4×b=779-3
4×b=776
b=776:4
b=194
2)20:a×35=700
20:a=700:35
20:a=20
a=20:20
a=1
3)16×a:8=32
16×a=32×8
16×a=256
a=256:16
a=16
5)a:13×9=819
a:13=819:9
a:13=91
a=91×13
a=1183
6)16×12:a=6
12:a=16×6
12:a=96
a=96:12
a=8