Question

Five donuts and 3 cinnamon rolls cost $11.50. Eight donuts and 6 cinnamon rolls

cost $20.50. How much does a donut cost? How much does a cinnamon roll cost?

Answer 1

The cost of one donuts is $1.25 and the cost of one cinnamon is $1.75

Explanation:

Let

x-----> the cost of one donuts

y ----> the cost of one cinnamon

we know that

`5x+3y=11.50` -----> equation A

`8x+6y=20.50` -----> equation B

Solve the system by graphing

Remember that the solution of the system of equations is the intersection point both graphs

using a graphing tool

The solution is the point (1.25,1.75)

see the attached figure

therefore

The cost of one donuts is $1.25 and the cost of one cinnamon is $1.75