Either way, one egg is missing, so if there is another egg, it can be counted accurately, so the number of eggs after adding one is not only a multiple of 3, but also a common multiple of 4,5, that is, a common multiple of 3,4,5. The common multiple of 3,4,5 is 60, 120,180,240,300, so the total is 300- 1=299.