Question 27857
First equation: 
4x+3y=320
Second equation:
5x+4y=406


Solve by elimination method.
Mulitply equation 1 by 4 and equation 2 by 3


4(4x+3y=320)
3(5x+4y=406)



16x+12y=1280 (1)
15x+12y=1218 (2)


Subbtract 1 by 2
x=62


solve for y
4(62)+3y=320
248+3y=320
3y=72
y=24


Hence,  about $24--> dinner cost.
Paul.