How to Count the Dots on a Basketball

When a basketball player's palms sweat, a basketball without dots or pebbles gets slippery and hard to control. Pebbles combat the problem created by sweaty palms. To count the number of pebbles on a basketball, use the surface area of the basketball.

Difficulty: Moderately Easy

Instructions

1. Measure the circumference of the basketball with a string or a tailor's measuring tape. If you use a string, loop the string tightly around the center of the ball and then lay the string flat along a measuring tape to find the circumference.

2. Convert the circumference of the basketball to the radius. The radius is half the length of the diameter. Use the formula that diameter equals circumference divided by pi (d=c/pi) then divide by 2 for the radius. On an NBA regulation basketball, the diameter equals 29.5 inches, so the radius equals 4.70 inches.

3. Calculate the surface area by multiplying 4 by 3.14 (pi) by the radius squared. Taking the calculations from Step 2 we arrive at a surface area of 277.45 square inches.

4. Mark a one inch square on the basketball and manually count the dots in the area. Once you know the number of pebbles in your area multiply that number by the number of pebbles in your measurement area. For example, if you conclude that there are 99 pebbles in your square inch, you would have a rough estimate of 27,467.59 pebbles on the ball.

5. Count the dots manually. Take a red marker and touch each dot as you count. You may want to write down the number as you go so you don't lose your place. To double-check the number of pebbles, go back over the entire surface using a black marker.

Tips & Warnings

• Make the best square inch possible considering you are trying to draw a straight line on a rounded surface.
• The exact specifications vary depending on the manufacturer.
• The surface area provides a rough estimate, but manually counting the pebbles twice should give you the actual number.