How many meli meter equals 1 decimal?

Answer 1

None, for the following reasons:

First, there is no such thing as a meli meter - perhaps you mean millimetre, which is a measure of length. Let us assume that you made a spelling error.

A decimal can either be a way of representing a number in such a way that the place value of each digit is ten times that of the digit to its right. In that case, it is a pure number and has no dimensions of length and, according to the basic rules of dimensional analysis, conversion from one to the other is not valid.

Alternatively, a decimal is a measure of area, used mainly in South Asia. This has dimensions of Length2 and since that is different to the dimensions for a millimetre, again according to the basic rules of dimensional analysis, conversion from one to the other is not valid.