a pound to a penny
bet (someone) a pound to a penny
To be convinced that something is very probable or likely (to happen or be the case). Primarily heard in UK. I've been hearing about layoffs and pay cuts for a while now, but I bet you a pound to a penny that none of the executives see a drop in their salaries. I'd bet a pound to a penny this issue was caused by a computer virus someone accidentally downloaded.
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.
a pound to a pennyit is extremely likely. informal
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