Bet (someone) a pound to a penny British verb phrase
If a person "bets someone a pound to a penny", he or she tries to make someone believe that something will likely happen.
She bet me a pound to a penny that my roommate had stolen my money.
I'd bet you a pound to a penny that our teacher hasn't read our essays yet.
The verb "bet" should be conjugated according to its tense.
A person who is completely unknown or has no connection with you
The guy I talked to at the prom last night is a perfect stranger.