19.98×37-199.8×1.9+1998×0.82 888+32×0.125×0.25 7.8÷[32×(1-5/8)+3.6] 1/1×2+1/2×3+1/3×4+…+1/99×100.
问题描述:
19.98×37-199.8×1.9+1998×0.82 | 888+32×0.125×0.25 | ||||||||||
7.8÷[32×(1-
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答
(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),=8...