1. Calculate the Volume in Cubic Inches:
* Multiply the length, width, and height: 30 inches * 12 inches * 12 inches = 4,320 cubic inches
2. Convert Cubic Inches to Gallons:
* There are 231 cubic inches in one gallon.
* Divide the volume in cubic inches by 231: 4,320 cubic inches / 231 cubic inches/gallon = 18.7 gallons (approximately)
Therefore, a 30x12x12 tank holds approximately 18.7 gallons of water.