Answer:
60
Step-by-step explanation:
The small triangle has a perimeter of 7 inches.
So, since you can fit 3 triangles down the left side of the triangle, you would multiply 7 by 3 to get 21.
Then, since the other side is the same length, multiply 21 by 2 to get 42.
Next, you add 18 to 42 because at the bottom of the picture, it says 18 inches.
That's how you get a perimeter of 60 inches.
