How many cubic feet 3-4" deep will a ton of pea gravel cover?

One cubic yard (27 cubic feet) of pea gravel weighs about 3,000 lbs
One cubic foot weighs 111.11 lbs 3000/27
There are 18 cubic feet in one ton of pea gravel 2000/111.11
18 cubic feet at 3 1/2 inch (0.29 feet) depth will cover 62 square feet 18/0.29

For example: If 4 feet wide, one ton will cover a length of 15.5 feet 62/4

smearcase, you done a lot of research here. Kudos.

Have a garden area that is about 140 sq ft and want to determine how much pea gravel I will need to cover it, at a 2-3 inch depth. This is for ground covering in a planting bed, not a walking path. Thanks!