One side of the rectangle is 7 decimetres and the other 5 decimeters and 3 cm. Calculate the perimeter of the rectangle

Let’s express the length of the second side of this rectangle in decimeters.
According to the condition of the problem, the length of the second side of this rectangle is 5 decimeters and 3 centimeters.
Since there are 10 centimeters in one decimeter, the length of the second side of this rectangle in decimeters is:
5 dm + 3 cm = 5 dm + 0.3 dm = 5.3 dm.
Find the perimeter p of a given rectangle as the doubled sum of the length and width of this rectangle:
p = 2 * (7 + 5.3) = 2 * 12.3 = 24.6 dm.
Answer: the perimeter of this rectangle is 24.6 dm.