Answer:
2.5 hours
Explanation:
The total amount of time studying by students who spent 1/2 an hour studying is the product of the number of students who spent 1/2 an hour studying by 1/2 an hour.
Hence, counting the number of dots on the point marked 1/2 gives the count of students who spent 1/2 an hour studying and multiply this number by 1/2.
Total amount of hours spent = 1/2 * 5 = 2.5 hours