If, a unit increase in one is accompanied by the same positive increase in the other (whatever the starting value), and when one is zero the other is also zero.
In algebraic terms, if x and y are the two variables, and their relationship is given by
y = f(x)
then the first condition states that dy/dx is a positive constant, say m. Equivalently, the relationship is the linear function,
y = mx + c.
The second condition then states that the intercept term, c, is zero.
Thus the relationship reduces to y = mx.
They vary proportionally if (and only if) the graph of one variable against the other is a straight line through the origin.
a variable
Variable: A letter or symbol used to represent a number or quantities that vary
Two quantities are proportional if they vary in such a way that one of them is a constant multiple of the other.
In mathematics, two quantities are proportional if they vary in such a way that one of them is a constant multiple of the other.
They vary proportionally if (and only if) the graph of one variable against the other is a straight line through the origin.
If you vary only one quantity in an experiment, then the results will be related to that quantity. If you vary two or more quantities, then the results will be ambiguous; you will not know what variation is responsible for the observed result.
Bar graph
A bar graph.
Two quantities are said to be proportional if they vary in such a way that one of the quantities is a constant multiple of the other, or equivalently if they have a constant ratio.
The units will vary, depending on what you want to measure.
a variable
It is necessary to know the magnitude and the direction of the vector.
Two quantities are proportional if they vary in such a way that one of them is a constant multiple of the other.
Variable: A letter or symbol used to represent a number or quantities that vary
As one measure increases the other measure decreases proportionally. An example would be temperature vs clothing. The hotter it gets, the less people wear.
haha, you would be proportionally larger, and wouldn't know the difference =)