Take the Log(base 10) of: 101^50 =100.21606868913212871375940891115
Take the Log(base 10) of: 99^50 + 100^50 =100.20547667843520423239829164658
Subtract the second from the first =0.01059201069692448136111726456409
Raise this difference to the power of 10: 10^0.01059201069692448136111726456409
Answer of above calculation =1.0246888504147627173327968676126 - 1 x 100
2.4688850414762717332796867612636 % =~ 2.5 % .
That is: 101^50 is about 2.5% bigger than the sum of [99^50 + 100^50]