The answer will depend on the units used for 300 and 275: inches, feet, yards, metres? Since you have not bothered to share that crucial bit of information, I cannot provide a more useful answer.
3.49 acres
1.2144168 ACRES.
1.107 acres, approx.
A lot that is 300 feet by 80 feet is equal to 0.55 acres.
50,000 square feet is 1.15 acres.
15,400 square feet is 0.35 acres.
57,200 square feet is 1.31 acres.
13,674 square feet is ~0.31 acres.
30,855 square feet is 0.71 acres.
20,701 square feet is ~0.48 acres.
16,500 square feet is ~0.38 acres.
42,336 square feet is 0.97 acres.