Problem 4. On the math test, the teacher set 30 problems. The number of problems correctly solved by a student is 20 more than the number of problems not solved. For each correctly solved problem, the student gets 8 points, and for each unsolved or incorrectly solved problem, the student loses 3 points. How many points in total did the student score on the math test?
Solution. The number of unsolved problems is $(30-20): 2=10: 2=5$ problems. Then, the number of correctly solved problems is $30-5=25$ problems. Since, for each correctly solved problem, the student receives 8 points, and for each unsolved problem, loses 3 points, the total number of points the student earned is $8 \cdot 25-3 \cdot 5=200-15=185$ points.