Small Differences: Denominations

I am being scuppered by denominations here.  Not religious ones, you understand: coins.  Seriously, my kids can make change here better than I can.  Obviously they had only just embarked on having to use coins in Scotland so it has not been such a big deal to toss that little slither of learning out of the window and start from scratch with American coins.  For me, however, I am having to undo a few decades’ worth of knowledge, something that had become reflex, and learn something new.  Apparently my brain is not coping very well with that.  It’s all about the denominations.  In Britain we have 1 pence, 2p, 5p, 10p, 20p, 50p and £1 coins; in America those denominations are 1 cent, 5 cents (nickel), 10 cents (dime) and 25 cents (quarter).  There are also half and whole dollar coins but those are rare so I am discounting them.  Clearly, therefore, I am used to adding and multiplying using different bases than are available here so all my maths (or math, as it is here) has to alter.  I am not innumerate so that it is not that I can’t do it but I am very conscious that it takes me more time to rake around in my purse (wallet, as it is here) to find the coins I need and tot them up to the amount I need.  And I have to keep reminding myself that the five cent coin is larger than the ten cent coin because they are the shape and size of UK five and ten pence coins but with the scale inverted.  Two university degrees mean nothing when you are at the head of a queue of people who are all aware that you are taking an awkward amount of time to fumblingly make 68 cents.