John Brandt, Age 10, Of Lancaster, Pa,., for his question:

Haw many hairs are on the head of an average person?

It would be a tiresome job to count the exact number of hairs on your head. Besides, a few fall out every day as new ones sprout, and today's count would be different tomorrow. But we can estimate the number of hairs on the average head, even though some hair is finer than others and more hairs are needed to cover the skin.

The head of the average person usually sprouts hair from an area of about 120 square inches. If the hairs are of medium thickness, there are about 1000 of them growing from each square inch of skin. So the average human head grows a thatch of about 120,000 separate hairs. Blond hairs tend to be finer than brawn or black hairs. A blondie as a rule has more than 120,000 hairs, and a very dark person is likely to have less than the average number.