The lengths of the sides of the rectangle are 5 cm and 12 cm. If you increase its width by 0.8 cm

The lengths of the sides of the rectangle are 5 cm and 12 cm. If you increase its width by 0.8 cm and its length by 0.6 cm, then determine the increment of the perimeter and area of the rectangle.

1. Let’s calculate what the perimeter P of the original rectangle is equal to if its length is 12 centimeters and its width is 5 centimeters.

P = 2 * 12 cm + 2 * 5 cm = 34 centimeters.

2. Let’s calculate the area S of this rectangle.

12cm * 5cm = 60cm ^ 2.

3. Let’s calculate what the perimeter P1 of the rectangle will be, if the length is increased by 0.6 centimeters, and the width by 0.8 centimeters.

P1 = 2 * (12 + 0.6) + 2 * (5 + 0.8) = 2 * 12.6 + 2 * 5.8 = 25.2 + 11.6 = 36.8 centimeters.

4. define the perimeter increment.

P1 – P2 = 36.8 cm – 34 cm = 2.8 cm.

5. Let’s calculate what will be equal to the area S1 of the resulting rectangle.

S1 = 12.6cm * 5.8cm = 73.08cm ^ 2.

6. Let’s define the increment of the area.

S1 – S = 73.08 cm ^ 2 – 60 cm ^ 2 = 13.08 cm ^ 2.

Answer: The perimeter increment is 2, 2 centimeters, and the area is 13.08 square centimeters.