Given:
The table of values is
Number of Students : 7 14 21 28
Number of Textbooks : 35 70 105 140
To find:
The rate of change and showing that the ratios of the two quantities are proportional and equivalent to the unit rate.
Solution:
The ratio of number of textbooks to number of students are
[tex]\dfrac{35}{7}=5[/tex]
[tex]\dfrac{70}{14}=5[/tex]
[tex]\dfrac{105}{21}=5[/tex]
[tex]\dfrac{140}{28}=5[/tex]
All the ratios of the two quantities are proportional and equivalent to the unit rate.
Let y be the number of textbooks and x be the number of students, then
[tex]\dfrac{y}{x}=k[/tex]
Here, k=5.
[tex]\dfrac{y}{x}=5[/tex]
[tex]y=5x[/tex]
Hence the rate of change is constant that is 5.
