When I was nine I did a standardised reading test in school and came out with a reading age of sixteen. Not surprising as I read more than anyone could without becoming a social recluse. If you had reversed the ages, most people would be alarmed, and I’d probably be the subject of ridicule besides. Alex Thompson did a great piece on failing literacy standards in UK primary schools back in 2007. I reckon even the chavs would make fun of each other if they found an illiterate in their midst, although I’m too cowardly to have asked. They were bigger boys!
When it comes to innumeracy though, it seems it’s both socially acceptable at all ages and a source of pride for some. But numbers, like text, are everywhere. No one’s saying we should all be able to do linear algebra in our sleep, but anecdotally I can think of some ridiculous demonstrations of the failure to grasp maths concepts that should have been mastered in primary school.
I recall an old school friend saying that mixing drinks is bad because “if you mix one drink that’s 30% with one that’s 40%, that’s like 70%”. WHAT? HOW CAN YOU FUNCTION? You probably think playing the same lottery numbers every week is a winning strategy too.
Indirectly it also limits understanding of some aspects of natural sciences, as you can’t handle the foundational maths involved. Again, not everyone needs to understand advanced chemistry, but it’s good for your health and your pocket if you can understand molar masses and why this helps us see that homeopathy is 100% insanity.
Lots and lots and lots of people had a terrible time with maths in school, be it from teachers or uninspiring curricula. It’s never too late to start again though, especially with so many free resources. Start with Khan Academy – it’s great because you’ll see exactly where your teacher abandoned you before, and see how everything progresses from the most basic number line all the way to stuff you’d be learning in the beginning of a university degree. Want to go further? Perhaps Coursera or Udacity.
Never stop learning. Good luck.