Answer: A. 'x' be the number of doughnuts sold and 'y' be the number of cartoons of milk sold.
B. [tex]x+y=85[/tex]
[tex]1.35x+1.08y=104.49[/tex]
C. x=47 and y=38
D. The number of doughnuts sold x= 47 and the number of cartoons of milk sold= 38.
Step-by-step explanation:
A. Since there are only two quantities i.e. doughnuts and cartons of milk.
So let 'x' be the number of doughnuts sold and 'y' be the number of cartoons of milk sold.
B. The total number of items sold = [tex]x+y=85[/tex]
The total amount they earned=[tex]1.35x+1.08y=104.49[/tex]
∴ The system of equations that model the problem will be
[tex]x+y=85[/tex].........(1)
[tex]1.35x+1.08y=104.49[/tex].............(2)
C. To apply linear combination method multiply eqn(1) by 1.5 we get
[tex]1.35x+1.35y=114.75[/tex]....(3)
Now subtract eq(2) from eqn(3), we get
[tex]0.27y=10.26\\\Rightarrow\ y=\frac{10.26}{0.27}\\\Rightarrow\ y=38[/tex]
From (1), we get x=85-38=47
D. From C part the number of doughnuts sold x= 47 and the number of cartoons of milk sold= 38.