The ratio of students failing the test to students passing the test was 2 to 9 they were 143 students who took the test how many did not pass
The ratio of students failing the test to students passing the test is 2 to 9. This means that out of every 2 + 9 = 11 students, 2 of them failed the test.
So, if there were a total of 143 students who took the test, then the number of groups of 11 students is 143/11 = <<143/11=13>>13.
This means that there were 13 x 2 = <<13*2=26>>26 students who failed the test.
Therefore, 143 - 26 = <<143-26=117>>117 students did not pass the test. Answer: \boxed{117}.