Use the form below to do your conversion.
Solution
Step1
Log219991=Log(9991) ÷ Log(21)
Log(9991)= 3.9996089589714
Log(21)=1.3222192947339
Log219991=3.9996089589714 ÷ 1.3222192947339
Ans=3.0249210360951
Step2
Alternatively, the logarithm can be calculated like this.