Final answer:
For each set of 4 incorrect problems, Josie has 9 correct problems. With 8 incorrect problems, this means Josie has 2 sets of correct answers, resulting in 18 (2 times 9) correct problems.
Step-by-step explanation:
The question asks to find out how many problems Josie got correct on a test given the ratio of incorrect to correct answers is 4:9 and the number of incorrect answers is 8.
To solve this, consider that for every 4 incorrect problems, there are 9 correct ones.
Since Josie missed 8 problems, we have two groups of incorrect answers (8 divided by 4 equals 2), so there must be two groups of the correct answers as well (2 times 9).
Therefore, Josie got 18 (9 multiplied by 2) questions correct, which corresponds to option B.