Question

On Monday, Joe bought 10 cups of coffee and 5 doughnuts for his office at the cost

of $16.50. It turns out that the doughnuts were more popular than the coffee. On
Tuesday, he bought 5 cups of coffee and 10 doughnuts for a total of $14.25. How much is each doughnut?

Answer 1

X= be coffee

Y=be donuts

Set up equations

10x+5y=16.50

5x+10y=14.25

Now multiply first equation by -2 to get a negative

(-2)10x+5y(-2)=16.50(-2)

-20x-10y=-33

Now put both equations to solve for x

-20x-10y=-33

5x+10y=14.25

___________

-15x. = -18.75

Now divide -15 bith sides to get x alone

X= -18.75/-15

X= 1.25

The cost of each coffee cup$1.25

Hope this helps!!