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19.98×37-199.8×1.9+1998×0.82 888+32×0.125×0.25 7.8÷[32×(1-58

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19.98×37-199.8×1.9+1998×0.82 888+32×0.125×0.25
7.8÷[32×(1-
5
8
19.98×37-199.8×1.9+1998×0.82 888+32×0.125×0.25 7.8÷[32×(1-58
(1)19.98×37-199.8×1.9+1998×0.82,
=19.98×37-19.98×19+19.98×82,
=19.98×(37-19+82),
=19.98×100,
=1998;
(2)888+32×0.125×0.25,
=888+(8×4)×0.125×0.25,
=888+(8×0.125)×(4×0.25),
=888+1×1,
=888+1,
=889;
(3)7.8÷[32×(1-
5
8)+3.6],
=7.8÷[32×
3
8+3.6],
=7.8÷[12+3.6],
=7.8÷15.6,
=0.5;
(4)
1
1×2+
1
2×3+
1
3×4+…+
1
99×100,
=(1-
1
2)+(
1
2-
1
3)+(
1
3-
1
4)+…+(
1
99-
1
100),
=1-
1
2+
1
2-
1
3+
1
3-
1
4+…+
1
99-
1
100,
=1-
1
100,
=
99
100.