Final answer:
Jake got 17 questions correct on the math test.
Step-by-step explanation:
To find out how many questions Jake got correct on the math test, we need to calculate 85% of 20. To do this, we multiply 85/100 by 20: 85/100 * 20 = 0.85 * 20 = 17. Therefore, Jake got 17 questions correct on the math test.