Answer:
10%
Explanation:
To find the probability that a student earns a grade of D, you'll need to use the formula for probability:
Probability = (Number of favorable outcomes) / (Total number of possible outcomes)
In this case, the favorable outcome is a student earning a grade of D, and the total number of possible outcomes is the total number of students.
Given the grade distribution:
Grade D Frequency = 14 (Number of favorable outcomes)
Total number of students = Sum of the frequencies for all grades = 28 + 35 + 56 + 14 + 7 = 140
Now, plug these values into the probability formula:
Probability of earning a grade of D = (Number of D grades) / (Total number of students)
Probability of earning a grade of D = 14 / 140
Calculate the probability:
Probability of earning a grade of D = 0.1
So, the probability that a student earns a grade of D is 0.1, or 10%.