2.7870912
(29' x 50' x 5/12') x (1,728 cubic inches per cubic foot) / (231 cubic inches per gallon) =4,519.48 gallons (rounded)
Cannot be answered with only these measurements. You need to specify what shape the pool is. Also, for a rectangular pool, the length, width and depth are needed. For a round pool, the diameter and depth are needed.