The rectangle is 20 mm wide and 25% longer in length. find the perimeter and area of the given rectangle.

1. Find 25% of the width of the rectangle:
(20 mm / 100) * 25 = 0.2 * 25 = 5 mm.
2. Since the length is 25% more than the width, add 25% to the width and find the length:
20 mm + 5 mm = 25 mm.
3. Find the perimeter and area of the rectangle by the formulas P = 2 * (a + b), S = a * b, where P is the perimeter of the rectangle, S is the area of a rectangle with length a, width b:
P = 2 * (25 + 20) = 2 * 45 = 90 mm.
S = 25 * 20 = 500 mm2.
Answer: the area of this rectangle is 500 mm2, and the perimeter is 90 mm.