Final answer:
Mark got 24 questions correct on the first-quarter math CSA.
Step-by-step explanation:
To find the number of questions Mark got correct, we can use the percentage score and the total number of questions on the test. Mark scored 80%, so we can calculate the number of questions he got correct as follows:
Number of questions correct = Percentage score * Total number of questions
Number of questions correct = 0.8 * 30 = 24
Therefore, Mark got 24 questions correct on the first-quarter math CSA.