Here's the issue: in Australian English (and British English) the word 'couple' is always followed by 'of' when used as a collective noun: 'a couple of days', 'a couple of idiots'. American English has seemingly dropped that requirement, resulting in such oddities as 'a couple weeks' and 'a couple problems'. I accept that spelling and grammar vary between dialects and change over time. Just don't expect me to go along with this particular horror.
Picture by Dan Kitwood/Getty Images
It's certainly an illogical and inconsistent position. As far as I'm aware, no-one in America would skip the 'of' in an expression after similar collective nouns such as 'pair' or 'number'. However, illogical and inconsistent rules abound in most languages, whichever variant you favour.
If the American people want to write 'a couple times', I won't stand in the way. But I won't stand for it in written Australian English, especially in a professional context.
I mention this merely because we're all now so frequently exposed to the American usage online. As with other variations, there's a danger that ill-informed writers will assume this is acceptable behaviour. It simply isn't in an Australian context. It's not a difficult rule to remember; it should take no more than a couple of minutes to absorb. Do so!
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