Is 0.3 equivalent to 0.30

Answer 1

Mathematically, the two numbers are equivalent.

If you encountered these two numbers in a scientific context, however, the fact that they have different numbers of significant digits would probably be relevant. 0.30 has one more significant digit than 0.3, and this difference indicates that 0.30 represents a more precise measurement. The natural assumption, then, is that 0.3 and 0.30 are not the same, although they might be - that is, it's possible that the quantity measured as 0.3 might have been measured as 0.30 if a more precise measurement tool had been used, but it's also possible that the more precise measurement would have yielded a result like 0.31 or 0.29 instead.

Answer 2

yes

Answer 3

yes