Answer/Step-by-step explanation:
==>The median hours for each category students can be easily gotten by observing the dot plot and finding where the middle value falls on.
For 5th grade students, since the number of data set is an even number (24), the median lies between the 12th and the 13th dot if we count from our left. The 12th and 13th dot represents 5 hours. Our median would be the average of the 12th and 13th value. Thus we have (5+5)/2 = 5.
If we follow the same method for the 7th grade students, our 12th and 13th value would be 3 and 4 respectively. Median for 7th grade is (3+4)/2 = 3.5.
Comparing the medians of 5th and 7th grade students, 5th grade students has a higher median of 5hours compared to 3.5hours for 7th grade students.
==>5th grade range = highest hours - lowest hours = 8-1 = 7
==>7th grade range= 7-0 = 7
==>Ratio of variation of 5th grade to 7th grade = 7:7 = 1