Last year, Bob's Auto Supplies sold 120 air filters out of a total of 3000 items sold. Bob will show his sales in a circle graph. Find the measure of the central angle that will represent the air filter category.

Assuming that bob will use a circle with radius 1 unit,

then the area of the whole circle is A = pi R^2

A = 3.1416 (1^2)

A = 3.1416

fraction of auto supplies = 120 / 3000 = 0.04

Area auto supplies = 3.1415 (0.04) = 0.1257

formula for of a circular segment

A = 0.5r^2x

where x is the angle in radian

0.1257 = 0.5 (1^2) x

x = 0.2513 rad

convert to degrees

x = 0.2513 rad (180 / pi)

x = 14.40 degrees