1. He has four balls. One is white, another is blue, another is green, and the other is yellow.

2. He has four balls. One is white, another is blue, a third is green, and the other is yellow.

3. He has four balls. One is white, another is blue, a third is green, and the fourth is yellow.

4. He has four balls. One is white, a second is blue, a third is green, and the other is yellow.

5. He has four balls. One is white, a second is blue, another is green, and the fourth is yellow.
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Are they all grammatical? Which ones are commonly used?

1 answer

All are grammatically correct.

#3 is probably most used, but there are variations.