Given diagonal (PR) = 41 cm, length (PQ) = 40 cm Let breadth (QR) be x cm. Now, in right angled triangle PQR,

Therefore the breadth of the rectangle is 9 cm.

Perimeter of rectangle = 2(length + breadth)

= 2 (9 + 40) = 2 x 49 = 98 cm

Hence the perimeter of the rectangle is 98 cm.