Okay, so if your rectangle is 16 by 8, that means that the circle diameter of 8 because that would be outside of the card's width, the area of the rectangle is 16 x 8 or 128 the radius of the circle would be 4 (because 1/2 of the diameter is radius) we know that the equation of the circle PIr^2, so the area of the circle is 16PI then, the remaining area would be calculated by 128-16PI This comes out to be approximately 77.73