On the quantitative relationship and formula of positive proportion and inverse proportion?

The change law of two related quantities is in direct proportion: it expands at the same time and contracts at the same time, and the ratio remains unchanged. X/Y = K (sure);

The change law of two related quantities is inversely proportional: one becomes larger and the other becomes smaller; Anyway, one gets smaller and the other gets bigger. The law is that the product of the two is constant. X× y = k (determined);

Extended data:

meaning

Two variables that satisfy the relation y = k x (k is a certain quantity) are said to be proportional.

Obviously, if y is proportional to x, then y/x=k(k is a constant), and vice versa.

For example, if the speed is constant, the distance is proportional to the time; In engineering problems, if the work efficiency remains unchanged, the total amount of work is directly proportional to the working time.

Note: k cannot be equal to 0.

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