9.99×22.2+33.3×3.34 1/3+1/15+1/35+1/63+1/99+1/143

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9.99×22.2+33.3×3.34 1/3+1/15+1/35+1/63+1/99+1/143

9.99×22.2+33.3×3.34 1/3+1/15+1/35+1/63+1/99+1/143
9.99×22.2+33.3×3.34 1/3+1/15+1/35+1/63+1/99+1/143

9.99×22.2+33.3×3.34 1/3+1/15+1/35+1/63+1/99+1/143
9.99×22.2+33.3×3.34
=33.3×6.66+33.3×3.34
=33.3×(6.66+3.34)
=33.3×10
=333

1/3+1/15+1/35+1/63+1/99+1/143=1/2x(1-1/3)+1/2x(1/3-1/5)+.....1/2x(1/9-1/11)+1/2(1/11-1/13)=1/2x(1-1/3+1/3-1/5+....+1/9-1/11+1/11-1/13)=1/2x(1-1/13)=1/2x12/13=6/13

9.99×22.2+3.33×3.34=33.3×3×2.22+33.3×3.34=3.33×(6.66+3.34)=33.3
1/3+1/5+1/35+1/63+1/99+1/143=1/3+1/2 (1/3-1/5+1/5-1/7+1/7-1/9+1/9-1/11+1/11-1/13)=11/26