Answer:
Equation is 4 p-3=11
Explanation:
Barbara is buying 4 binders each cost same amount.
Let the cost of 1 binder is '$p'.
So, cost of 4 binders = $4 p.
Now, a coupon that gives her $3 off.
So, Barb needs to pay 4 p-3 dollars.
Barb pays a total of $11 when the value of the coupon is subtracted.
So, we can set up equation as
4 p-3=11