Depending on the process you use to combine them, it could be called addition,
subtraction, multiplication, division, averaging, exponentiation, etc.
Combining two or more numbers to find the sum is called addition.
Multiplying. Yes, multiplication.
Factors. When two numbers are multiplied, the answer is called the product.
When you multiply two numbers, it is called the product.
The two (or more) numbers that you multiply are called factors. (The result of the multiplication is called the product.)
Combining two or more numbers to find the sum is called addition.
concatination
ratio
quotient
It is called multiplication.
Combining two atomic nuclei is called nuclear fusion.
The process of adding two or more numbers together is called addition.
sum
An Emulsion is the process of combining two liquid's. One of which having a much higher fat content . This is combining the two with out having them separate once left alone. This is a somewhat gradual process.
You may be thinking of the term, "Ratio".
ratio
Multiplying. Yes, multiplication.