RichThesaurus
a pound to a penny
vs
bet a dollar to a doughnut
a pound to a penny
adv
Very likely; almost certainly.
bet a dollar to a doughnut
verb
To declare with confidence.
How often have the words
a pound to a penny
and
bet a dollar to a doughnut
occurred in a corpus of books?
(source:
Google Ngram Viewer
)