Of the total area that is used by humans (Agriculture, Urban and Built-up Land),
- urban and built-up land is 1m km²,
- agriculture is 48m km²,
so agriculture is 48 of 49 millions km² used, that’s 98%. The remaining 2% are all streets and housing and other infrastructure together.
It was the obvious joke reply. True or not, works either way. [Edit: and works either way as to whether replying to the original post or that reply.]