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• 1). Hold one end of your measuring tape in the center front of your chest, just below your breasts. Make sure the measuring tape is flat and wrap it all the way around your rib cage and back until it meets the starting point in front. Write down the number of inches from the starting point to the point where the other side of the measuring tape meets the starting point.

• 2). Put this number into your calculator and add five. Write the answer to the equation on your paper. This is your band size for your bra. If you come up with an odd number round down to the closest band size. For example if you get a 35, wear a 34 bra.

• 3). Wear a bra, preferably padded, and measure the circumference of your bust at the fullest point. Write the number down on paper.

• 4). Put the number you got for your bust size into your calculator, then subtract the number you calculated for your band size. If the difference between the two numbers is less than an inch you are a AA cup, 1 inch is an A cup, 2 inches B cup, 3 inches C cup, 4 inches is D cup, 5 inches DD or E, and 6 inches F cup.

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