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简算2到,不难1,9.75+99.75+999.75+9999.75=2,1972×99.75+197.2×1.9+98

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简算2到,不难
1,9.75+99.75+999.75+9999.75=
2,1972×99.75+197.2×1.9+986×125.62=
简算2到,不难1,9.75+99.75+999.75+9999.75=2,1972×99.75+197.2×1.9+98
答案为:11109和320943
1,9.75+99.75+999.75+9999.75
= (10-0.25)+(100-0.25)+(1000-0.25)+(10000-0.25)
=10+100+1000+10000-0.25*4
=11110-1
=11109
2,1972×99.75+197.2×1.9+986×125.62
=197.2×997.5+197.2×1.9+986×0.2×628.1
=197.2×997.5+197.2×1.9+197.2×628.1
=197.2×(997.5+1.9+628.1)
=197.2×1627.5
=320943
就是这么简单