A waitress sold 18 ribeye steak dinners and 12 grilled salmon dinners, totaling $563.44 on a particular day. Another day she sold 26 ribeye steak dinners and 6 grilled salmon dinners, totaling $580.72. How much did each type of dinner cost?
Q. A waitress sold 18 ribeye steak dinners and 12 grilled salmon dinners, totaling $563.44 on a particular day. Another day she sold 26 ribeye steak dinners and 6 grilled salmon dinners, totaling $580.72. How much did each type of dinner cost?
Set up equations: Let's denote the cost of a ribeye steak dinner as R and the cost of a grilled salmon dinner as S. We can set up two equations based on the information given:1) 18R+12S=$563.442) 26R+6S=$580.72These equations represent the total sales for each type of dinner on two different days.
Use elimination method: We can use the method of substitution or elimination to solve this system of equations. Let's use the elimination method. We'll multiply the second equation by 2 to make the coefficient of S in both equations the same:2×(26R+6S)=2×($580.72)This gives us:52R+12S=($1161.44)
Subtract equations: Now we have the system of equations:1) 18R+12S=$(563.44)2) 52R+12S=$(1161.44)We can subtract the first from the second to eliminate S:(52R+12S)−(18R+12S)=$(1161.44)−$(563.44)This simplifies to:34R=$(598.00)
Solve for R: Now we can solve for R by dividing both sides of the equation by 34:3434R=34$598.00R=$17.59So, the cost of a ribeye steak dinner is $17.59.
Substitute back for S: Now that we have the value of R, we can substitute it back into one of the original equations to find the value of S. Let's use the first equation:18R+12S=$563.44Substituting the value of R gives us:18($17.59)+12S=$563.44Calculating 18 times $17.59 gives us:$316.62+12S=$563.44
Substitute back for S: Now that we have the value of R, we can substitute it back into one of the original equations to find the value of S. Let's use the first equation:18R+12S=$563.44Substituting the value of R gives us:18($17.59)+12S=$563.44Calculating 18×$17.59 gives us:$316.62+12S=$563.44Now we can solve for S by subtracting $316.62 from both sides of the equation:12S=$563.44−$316.6212S=$246.82Dividing both sides by 12 gives us:S=$246.82/12S=$20.57So, the cost of a grilled salmon dinner is 18($17.59)+12S=$563.440.