(1)
-7 5
÷2 5
-7 15
1 7
=
-7 5
×2 5
-15 7
1 7
=
-7 5
-6 7
1 7
=
-(7 5
+6 7
)1 7
=
-17 5
=
2 5
(2)(50×49×48)÷(16×15×14)
=(50÷15)×(49÷14)×(48÷16)
=
×10 3
×37 2
=35
(3)4.06×125%+7.36÷
-0.142×12.54 5
=4.06×1.25+7.36×1.25-1.42×1.25
=(4.06+7.36-1.42)×1.25
=10×1.25
=12.5
(4)
+1 2
+1 5
+1 8
+1 11
+1 20
+1 40
1 110
=(
+1 2
)+(1 5
+1 11
1 110