How do you judge whether the two quantities are in direct proportion or in inverse proportion?

How do you judge whether the two quantities are in direct proportion or in inverse proportion?

The positive ratio is y = KX. K > 0. X increasing y increasing
The inverse proportion is y = K / X. k > 0. X, increasing and decreasing
All of them are discussed as k > 0

How to judge whether the two quantities are in direct proportion or inverse proportion
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If when a becomes larger, B will also become larger, then B and a are in direct proportion, which is expressed as B = k * a (where k is a constant)
If B becomes smaller when a becomes larger, then B is inversely proportional to a, which is expressed as B = K / a (where k is also a constant)
I wonder if you understand?

Positive proportion and negative proportion judge whether the following two quantities are in proportion and which proportion?
The quality of salt is certain, and the salt content is similar to the quality of brine
The carrying capacity of the truck is fixed, the number of times and the number of times of carrying goods

The salt content is inversely proportional to the quality of salt water, and the number of times of transportation is inversely proportional to the quantity of salt water

How to judge whether the two quantities are in direct proportion or in inverse proportion? Give examples

Positive proportion: increases with the increase of independent variable
Inverse proportion: decreases with the increase of independent variable