If the area square 3 is 80 cm^2 and the area of square 2 is 100 cm^2, what is the area of square 1

Sherrie is baking a pie for her family. she leaves the room and comes back to 35% of the pie having been eaten before she can put the topping on. how much 1 square inch strips of dough will she need for the top, now that a portion is missing? round your answer to the nearest while nimber.