Hi btan219,
This is an example of a 'unit conversion' question. A number of questions on Test Day involve unit conversions (e.g. dollars to cents, hours to minutes, feet to inches, etc.).
Square centimeters and square millimeters are just different ways to measure area.
If you're not a big fan of the metric system, then try the following example:
1) Draw a 1 foot by 1 foot square. This is a "square foot" of area.
2) Since there are 12 inches in 1 foot, you can relabel the two measurements as "12 inches" and "12 inches"
3) 12 x 12 = 144, so this same space = 1 square foot = 144 square inches.
The exact same idea appears here, but we're dealing with metric measurements. Try drawing another picture, but using centimeters and millimeters (instead of feet and inches).
GMAT assassins aren't born, they're made,
Rich
im still not understand what they mean by square cm and square mm... how much is a square cm compared to a regular cm?
edit: ok i just kept reading your post until something clicked in my head. let me see if i understand this-
1cm by 1cm = 10mm by 10mm which is 100 square mm. since the area in cm is still 1 square cm, its 1/100=.01?