The area of the rectangle is 11.7dm, width is 2.6, all its sides are increased by 0.2dm, find the area of the rectangle.

According to the condition of the problem, the area of the rectangle is 11.7 dm, and its width is 2.6 dm.

Knowing what the area of this rectangle and its width are equal to, we find the length of this rectangle:

11.7 / 2.6 = 117/26 = 4.5 dm.

If all of this side rectangle is increased by 0.2 dm, then the length of this rectangle will be 4.5 + 0.2 = 4.7 dm, and the width of this rectangle will be 2.6 + 0.2 = 2.8 dm.

Then the area S of the resulting rectangle will be equal to:

S = 4.7 * 2.8 = 13.16 sq. dm.

Answer: the area of the resulting rectangle is 13.16 sq. dm.