WASHINGTON — It’s long been known that America’s school kids haven’t measured well compared with international peers. Now, there’s a new twist: Adults don’t either.

In math, reading and problem-solving using technology — all skills considered critical for global competitiveness and economic strength — American adults scored below the international average on a global test, according to results released Tuesday.

Adults in Japan, Canada, Australia, Finland and multiple other countries scored significantly higher than the United States in all three areas on the test. Beyond basic reading and math, respondents were tested on activities such as calculating mileage reimbursement due to a salesman, sorting email and comparing food expiration dates on grocery store tags.

Not only did Americans score poorly compared to many international competitors, the findings reinforced just how large the gap is between the nation’s high- and low-skilled workers and how hard it is to move ahead when your parents haven’t.

In both reading and math, for example, those with college educated parents did better than those whose parents did not complete high school.