[bradleyjg]

That's not true. The vast majority of adult Americans can read at an adequate level. Further, given time and incentive, most can write well enough to be understood, if not exactly to high grammatical standards. These facts are triumphs of the modern educational system.

However large numbers of adult Americans when faced with:

  3x - 7/3 = 4

could not solve exactly for x, no matter the time and incentives. It is hard to imagine how such a person would be able to learn to code, at least as long as programming languages look anything at all like those of today.