In the case of the figure on the left, each unit is equivalent to 4ft in length; therefore, when a new scale 1 unit:8 ft is applied, every 2 units in the figure on the left transforms into 1 unit in the figure on the right. (2*4in=8in)
Therefore, on the grid on the right, you need to draw a 10/2x10/2=5x5, a 5x5 square.
Draw a 5x5 on the right so as to solve the question.