Question

5+5/1×2+5/2×3+5/3×4+……5/99×100

Answer 1

5+5/1*2+5/2*3+.5/99*100=5*(1+1/1*2+1/2*3+...1/99*100)=5*(1+1-1/2+1/2-1/3+1/3-1/4+...+1/99-1/100)=5*(1-1/100)=99/20=4.45