=[1/100×(10+1)+1/10000×(10+1)]/[1/1000×(10+1)]
=(1/100+1/10000)×(10+1)/[1/1000×(10+1)]
=(1/100+1/10000)/(1/1000)
=(1/100+1/10000)×1000
=10+1/10
=10.1