问题
解答题
(0.3+0.
|
答案
根据题意可得:
(0.3+0.
)+(0.3×2+0.• 3
×3)+(0.3×3+0.• 3
×5)+…+(0.3×50+0.• 3
×99),• 3
=(0.3+0.3×2+0.3×3+…+0.3×50)+(0.
+0.• 3
×3+0.• 3
×5+…+0.• 3
×99),• 3
=0.3×(1+2+3+…+50)+
×(1+3+5+…+99),1 3
=0.3×[(1+50)×50÷2]+
×[(1+99)×50÷2],1 3
=0.3×1275+
×2500,1 3
=382.5+833
,1 3
=1215
.5 6