Use the form below to do your conversion.
Solution
Step1
Log21691=Log(691) ÷ Log(21)
Log(691)= 2.8394780473742
Log(21)=1.3222192947339
Log21691=2.8394780473742 ÷ 1.3222192947339
Ans=2.1475091603058
Step2
Alternatively, the logarithm can be calculated like this.