50 2.02 m
1.22 m
border
A special shape is 2.02 m long and 1.22m wide
A double row of tiles makes a border.
Each tile is 2 cm by 2 cm.
How many tiles are needed to make the border?
A 648
B 624
C 632
D 640
E 636

A. 648

Step-by-step explanation:

The special shape has a length of 2.02 m (202 cm) and width of 1.22 m (122 cm).

Given a tile of 2 cm × 2 cm, and that a double row of tiles make a border.

For a single row border,  

the number of tiles required for its length = 202 /2 = 101

the number of tiles required for its width = 122/2 = 61

For a single row border, the total number of tiles for the perimeter of the special shape = 2 (101 + 61)

                       = 324

The number of tiles for a single row border is 324.

The number of tiles required to make the double row of tiles border = 2 (324)

                            = 648

The number of tiles required to make the border is at least 648.

4sqrt5

step-by-step explanation:

the base has dimensions of 8 x 4, so the diagonal is 64 + 16 square rooted or 4sqrt5.