How many pennies are in a pound?
In one pound there is 452 pennies
Incorrect: I'm sure you know there are 100 pennies in a pound.
Well, I take your point, and I know terms such as this are international... but I still feel the most likely meaning here would be units of British money. Really, the question should, if talking about units of weight in imperial measurement, say "how many pennies would weigh approximately 1lb?"