Proportionality

Direct and Inversely Proportion

Keywords:

Direct Proportion

Two variables are direct proportional if there is always a constant ratio between them.
(As one variable increases, the other also increases.)

yx=k
y=k·xa cb da:b=c:da·d=b·c

(The direction of the arrows follows the growth of the variables.
When committing proportionality, follow the arrows direction!)

Example: more books - more money 2 books 6 10 books  x 2:10=6:xx=30

Inversely Proportion

Two variables are inversely proportional if the product of those variables is a constant.
(As one variable increases, the other decreases.)

y·x=k
y=kxa cb da:b=d:ca·c=b·d

(The direction of the arrows follows the growth of the variables.
When committing proportionality, follow the arrows direction!)


Example: more workers - less days 2 workers 20 days5 workers   x days2:5=x:20x=8