Answer: Total cost to make 12 pennants is $52.5.
Step-by-step explanation:
Since we have given that
There is a rectangle and a triangle.
Length of rectangle = 1 ft
Width of rectangle = 3 ft
So, Area of rectangle is given by

Base of triangle = 1 ft
Height of triangle = 1 ft
So, Area of triangle is given by

So, Total area of the pennants will be

Number of pennants = 12
Cost per square foot of pennant = $1.25
So, Total cost for 12 pennants is given by

Hence, Total cost to make 12 pennants is $52.5.