That was an interesting question. I had to go back to my online dictionary to figure it out. And I found some usage notes about farther/further.
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Hanuman_2000The correct sentence would be '' I walk 30 kms farther than him''. Answer 2.
Hello,
I walk 60 kms. He walks 30 kms. (make comaparative sentence using "far").
It means
1. I walk further than him.
2. I walk farther than him.
Which one is correct ?
Farther is used in the United States. Further is used in the UK http://grammarist.com/usage/farther-further/