Answer:
She has a total of $3.75 left
Step-by-step explanation:
Step 1
Express the amount of money Luis had in the beginning as follows;
A=E+R
where;
A=initial amount he had at the beginning
E=total expenditure
R=total remainder after spending
In our case;
A=(1×10)+(3×5)=$25
E=Amount spent at amusement park+amount spent on snacks
E=(12.75+8.50)=$21.25
R=unknown=r
Step 2
Substitute the values in the expression and solve for A;
25=21.25+r
r=25-21.25=3.75
r=3.75
She has a total of $3.75 left