To find the perimeter of a rectangle, we will use the following formula:

where a, b, c, and d are the lengths of the sides of the rectangle.

Now, we know the width of the rectangle is 6cm.  Because it is a rectangle, we know the opposite side is equal.  Therefore, the opposite side is also 6cm.  

We also know the length is two times the width.  Therefore, the length is 12cm.  Because it is a rectangle, we know the opposite side is equal.  Therefore, the opposite side is also 12cm.

Knowing this, we can substitute into the formula.  We get

To find the perimeter of a rectangle, we will use the following formula:

where a, b, c, and d are the lengths of the sides of the rectangle.

Now, we know the length of the rectangle is 8cm.  Because it is a rectangle, we know the opposite side is also 8cm.  We also know the width is half the length.  Therefore, the width of the rectangle is 4cm.  Because it is a rectangle, we know the opposite side is also 4cm.  Knowing this, we can substitute into the formula.  We get

To find the perimeter of a rectangle, we will use the following formula:

where a, b, c, and d are the lengths of the sides of the rectangle.

Now, we know the width of the rectangle is 4in.  Because it is a rectangle, we know the opposite side is also 4in.  

We know the length is 3 times the width.  Therefore, the length is 12in.  Because it is a rectangle, we know the opposite side is also 12in.  

Knowing all of this, we can substitute into the formula.  We get

To find the perimeter of a rectangle, we will use the following formula:

where a, b, c, and d are the lengths of the sides of the rectangle.

Now, we know the width of the rectangle is 8cm.  Because it is a rectangle, we know the opposite side is also 8cm.  We also know the length is three times the width.  Therefore, the length is 24cm.  Because it is a rectangle, we know the opposite side is also 24cm.  

Knowing all of this, we can substitute into the formula.  We get

To find the perimeter of a rectangle, we will use the following formula:

where a, b, c, and d are the lengths of the sides of the rectangle.

Now, let's look at the rectangle.

We can see the length is 9 inches.  Because it is a rectangle, the opposite side is also 9 inches.  We can see the width is 6 inches.  Because it is a rectangle, the opposite side is also 6 inches. 

Knowing this, we can substitute into the formula.  We get

To find the perimeter of a rectangle, we will use the following formula:

where a, b, c, and d are the lengths of the sides of the rectangle.

Now, we know the length of the rectangle is 8cm.  Because it is a rectangle, we know the opposite side is also 8cm.  We know the width of the rectangle is half the length.  Therefore, the width is 4cm.  Because it is a rectangle, the opposite side is also 4cm.

Knowing this, we can substitute into the formula.  We get

To find the perimeter of a rectangle, we will use the following formula:

where a, b, c, and d are the lengths of the sides of the rectangle.

Now, we know the length of the rectangle is 7in.  Because it is a rectangle, the opposite side is also 7in.

We also know the width of the rectangle is 4in.  Because it is a rectangle, the opposite side is also 4in.

Knowing this, we can substitute into the formula.  We get

To find the perimeter of a rectangle, we will use the following formula:

where a, b, c, and d are the lengths of the sides of the rectangle.

Now, we know the width of the rectangle is 4in.  Because it is a rectangle, we know the opposite side is also 4in.

We also know the length is three times the width.  Therefore, the length is 12in.  Because it is a rectangle, the opposite side is also 12in.

Knowing this, we can substitute into the formula.  We get

To find the perimeter of a rectangle, we will use the following formula:

Where a, b, c, and d are the lengths of the sides of the rectangle.

Now, we know the length of the rectangle is 12cm.  Because it is a rectangle, the opposite side is also 12cm.  We also know the width of the rectangle is a quarter of the length.  To find the width, we will divide 12 by 4.  Therefore, the width is 3cm.  Because it is a rectangle, the opposite side is also 3cm.

Knowing this, we can substitute into the formula.  We get

To find the perimeter of a rectangle, we will use the following formula:

Where a, b, c, and d are the lengths of the sides of the rectangle.

Now, we know the width of the rectangle is 7in.  Because it is a rectangle, the opposite side is also 7in.  We also know the length of the rectangle is three times the width.  Therefore, the length is 21in.  Because it is a rectangle, the opposite side is also 21in.

Knowing this, we can substitute into the formula.  We get