One side of the rectangle is 400 cm and the other 3 times larger. Calculate the area of the rectangle.

Let’s solve this task in steps and explain each of them in detail.

1) 400 * 3 = 1,200 millimeters – the second side of the rectangle, since it is 3 times longer than the length of the first side, equal to 400 millimeters;

2) 400 * 1,200 = 48,000 mm ^ 2 – the area of a rectangle with side lengths of 400 millimeters and 1,200 millimeters.

Answer: 48,000 mm ^ 2.