The average kitchen sink has a width of approximately 23.5 inches, a length of approximately 31.5 inches, and a depth of approximately 21 inches.
Multiplying these values together, we can see that the volume of the average kitchen sink is about 15545.25 cubic inches.
The conversion of cubic inches to liquid gallons is 1 cubic inch = approximately 0.004329 gallons.
Multiplying these numbers, we can see that 15545.25 cubic inches is the same as approximately 67.29538725 gallons. Now, we just have to multiply that number by 4, since there are 4 quarts in a gallon.
67.29538725 * 4 = 269.181549
It takes approximately 269.181549 quarts to fill the average kitchen sink.
Hope that helped =)
