To help Marvin figure out the payments for the taco sauce, we need to formulate an equation based on the given information:
1. Let's denote the initial cost of the taco sauce by \( c \).
2. The discount on the taco sauce is \( \frac{1}{4} \) of the initial cost, which is \( \frac{1}{4}c \).
3. There is also a coupon that provides an additional discount of $0.40.
4. The final cost of the taco sauce after applying both the discount and the coupon is $1.20.
So, we need an equation that represents the following:
- Initial cost minus the discount minus the coupon equals the final cost.
The equation that captures this situation is:
[tex]\[ c - \frac{1}{4}c - 0.40 = 1.20 \][/tex]
Therefore, the correct equation to help Marvin figure out the payments is:
[tex]\[ c - \frac{1}{4} c - 0.40 = 1.20 \][/tex]
