Answer:
Part 6) 177 boys
Part 7) a) 88 minutes b) 104.5 minutes
Part 8) 1 gallon
Explanation:
we know that
A relationship between two variables, x, and y, represent a proportional variation if it can be expressed in the form
or
Part 6)
Let
x ----> the number of girls taking classes at the school
y ----> the number of boys taking classes at the school
we know that
![(x)/(y)=(1)/(3)](https://img.qammunity.org/2020/formulas/mathematics/middle-school/ed694dmblg23cdw8q2at8jmf9ebqpzg7k7.png)
----> equation A
----> equation B
substitute equation A in equation B and solve for y
![y=236(3)/4](https://img.qammunity.org/2020/formulas/mathematics/middle-school/6a7hol3e7ftue2yrpfh631nrkpbhtmgjrk.png)
![y=177\ boys](https://img.qammunity.org/2020/formulas/mathematics/middle-school/i9rj6ojfx5rvui0zpgw5xux01nal3tx7u6.png)
Part 7)
Let
s ----> the number of seats
m ---> the number of minutes
we know that
---> equation A
Part a) At this rate, how long will it take to add 16 seats?
For s=16 seats
substitute in the equation A and solve for m
![m=16(11)/2](https://img.qammunity.org/2020/formulas/mathematics/middle-school/jwz4uj3nwyi7u099jm7678gzng2rika3jx.png)
![m=88\ min](https://img.qammunity.org/2020/formulas/mathematics/middle-school/tue61raafov4n50otj8k2z3tojf7razjby.png)
Part b) At this rate, how long will it take to add 19 seats?
For s=19 seats
substitute in the equation A and solve for m
![m=19(11)/2](https://img.qammunity.org/2020/formulas/mathematics/middle-school/84v9o9wxvug8a75erunpoapdk2ivto5n80.png)
![m=104.5\ min](https://img.qammunity.org/2020/formulas/mathematics/middle-school/olnfc5cpqen1ldbhlr91gmuw1jewtrxnc4.png)
Part 8)
Let
x ----> the number of gallons
y ----> the area is square feet
we know that
----> equation A
step 1
Find the area of the fence
![A=(26)(7)=182\ ft^2](https://img.qammunity.org/2020/formulas/mathematics/middle-school/tpu57uhzl8e8es5i13ppq52jw0wlech6py.png)
step 2
Determine how many gallons of paint Lisa will need
For y=182 ft^2
substitute in the equation A and solve for x
![(x)/(182)=(1)/(350)](https://img.qammunity.org/2020/formulas/mathematics/middle-school/4oz3l51bw3vgphjmry89s3kvxqihpl7evh.png)
![x=(182)/(350)](https://img.qammunity.org/2020/formulas/mathematics/middle-school/ugs2u66mi3a8px9z765rc00axk9f5c5mh0.png)
![x=0.52\ gal](https://img.qammunity.org/2020/formulas/mathematics/middle-school/no8gcl8z3hth9knqnml7xclb39w3nyngek.png)
Round to the nearest whole number
![x= 1\ gal](https://img.qammunity.org/2020/formulas/mathematics/middle-school/6fv1jq86nuq0skj9ksad5o5o4u38bnnuqr.png)