The British Journal of Tabloid Mathematics (aka The Sun), proposes a formula for the naughtiness factor of a low-cut dress:
where N is the number of nipples exposed, from zero to two, or expressed as fractions of nipple shown; P is the percentage of exposed frontal surface area; C is the cup size factor, set to 1 for an A-cup, 2 for a B-cup, 3 for a C-cup, and 5 for D-cup or greater; and B is the bust measurement in inches. The Sun claim that a value of O greater than 100 indicates obscenity.
The Sun claim that the Roberto Cavalli dress worn by Britney Spears this week "showed off around 70 per cent of her breasts, and experts at Wonderbra think she is a 32D. Without any nipple exposure, Britney’s formula works out as 0x70x(20x5+32)/75 = 123.2 ."
Unfortunately, the suggested formula entails that if zero nipples are exposed (N=0), then the naughtiness factor is always zero. I propose modifying the formula as follows:
This enables us to recover a value of O=123.2 for Britney's dress.