Grade 6 Math: Area of Rectangles and Squares

Grade 6 focus: The area of a rectangle is the number of unit squares that cover it. The formula is \(A = \ell \times w\) (length times width). A square with side length \(s\) has area \(A = s^2\).

Video lesson: Watch this Math with Mr. J tutorial on area of rectangles and squares.

Units matter

Area is in square units (square inches, square meters, etc.). If sides are in inches, area is in square inches.

Decimals and fractions

Multiply as with whole numbers, then count decimal places—or multiply numerators and denominators for fractional side lengths.

Example: rectangle \(2.5\) m by \(4\) m: \(A = 2.5 \times 4 = 10\) square meters.

Squares

For a square with side \(3\frac{1}{2}\) ft, \(A = \left(3\frac{1}{2}\right)^2 = \left(\frac{7}{2}\right)^2 = \frac{49}{4} = 12\frac{1}{4}\) square feet.

Common mistakes

• Confusing perimeter (\(2\ell + 2w\)) with area (\(\ell \times w\)).
• Forgetting to square the side for a square’s area.
• Mixing linear units with area units.

Real-world link

Flooring, painting, and tiling problems often ask for area—estimate first, then compute.