Answer:
The ratio of the number of boys to the number of girls in the 6th grade and 8th grade are proportional .
Step-by-step explanation:
As given
Enrollment at Roosevelt Middle School is being reviewed by the school staff.
As the table shown in the question.
Ratio of the numbers of girls and boys of 6th grade .
[tex]\frac{Number\ of\ girls}{Number\ of\ boys} = \frac{9}{12}[/tex]
Simplify the above
[tex]\frac{Number\ of\ girls}{Number\ of\ boys} = \frac{3}{4}[/tex]
Ratio of the numbers of girls and boys of 7th grade .
[tex]\frac{Number\ of\ girls}{Number\ of\ boys} = \frac{12}{18}[/tex]
Simplify the above
[tex]\frac{Number\ of\ girls}{Number\ of\ boys} = \frac{2}{3}[/tex]
Ratio of the numbers of girls and boys of 8th grade .
[tex]\frac{Number\ of\ girls}{Number\ of\ boys} = \frac{15}{20}[/tex]
Simplify the above
[tex]\frac{Number\ of\ girls}{Number\ of\ boys} = \frac{3}{4}[/tex]
Ratio of the numbers of girls and boys of 9th grade .
[tex]\frac{Number\ of\ girls}{Number\ of\ boys} = \frac{25}{36}[/tex]
Clearly as shown above the ratio of the number of boys to the number of girls in the 6th grade and 8th grade are proportional .
