50 :::::::::::))))))))))))))))))))))))))))))))
Answer:
16 problems.
Step-by-step explanation:
100% divided by 20 questions.
100/20 is equal to 5, therefore each question is worth 5 points.
Grade of 80% divided by points per question.
80/5 is 16 so the student answered 16 questions correctly.
This is how you would solve the question.
600 mm of rain / 30 min = 50 mm of rain per minute
