Answer: Maria has 10 bills of 5€ and 10 bills of 10€.
She has a total of 150€.
Step-by-step explanation:
Let be "f" the number of 5€ bills that Maria has and "t" the number of 10€ bills that Maria has.
Set up a system of equations:

Use the Substitution method to solve the system of equations:
1. Solve for "f" from the first equation:

2. Substitute the equation obtained into the second equation and solve for "t".
Then:

3. Substitute the value of "t" into the equation
and evaluate:

Therefore, Maria has 10 bills of 5€ and 10 bills of 10 €.
So the total amount of money she has, is:

She has a total of 150€.
4y= -3x+15
y= (-3/4)x+15/4
y+2= (-3/4)(x-8)
y+2= (-3/4)x+6
y= (-3/4)x+4
8/185 = 4.3 %
That is the number of days she missed so she was in attendance
100-4 = 96%
Can you tell me by how many dollars has the price risen