0.11+0.22+0.33+0.44+0.55+0.66+0.77+0.88+0.99
=(0.11+0.99)+(0.22+0.88)+(0.33+0.77)+(0.44+0.66)+0.55
=1.1+1.1+1.1+1.1+0.55
=1.1×4+0.55
=4.4+0.55
=4.95