Steve makes an error during the world record episode

There’s bacteria that have better lives than this.

You've got too much time on your hands boy. sniff.

I don’t think he makes an error, I think he realises Karl wasn’t listening to he asks Karl how many he thinks.

That’s why he laughs when Karl says 5 because Steve literally already said how many it was.

See: what are the things in Gremlins called?

'I can't do this either'

That Sony's ours.

I think the 'what do you reckon?' is Steve asking if Karl thinks he can beat three. Karl just wasn't listening and thought he was asking how many.

Ricky has never been a good writer, his character Steve making this error is yet another example of that.