Calculate the perimeter of a rectangle if its two adjacent sides are equal to 7 cm 3 mm.

First of all, since different lengths appear in the task, we will establish a relationship between these values:

1 cm = 10 mm.

Thus, taking into account this ratio, we translate the length of the longer side into millimeters:

7 cm = 7 * 10 mm = 70 mm.

Now you can calculate the perimeter of the rectangle. Let’s define it by the following formula:

P = 2 * (a + b).

Let’s apply this formula:

P = 2 * (70 + 3) = 2 * 73 = 146 (mm).

If you need an answer in cm, just divide it by 10 (we get 14.6 cm).

Answer: 146 mm.