x and y are in direct proportion if xy=constant
True
False
x and y are in direct proportion if x/y = constant.
If x, y and z are in continued proportion then z:x::z2:y2.
Continued proportion means a:b : : b:c
Two quantities x and y are said to vary in inverse proportion, if there exists a relation of the type xy = k between them, k being a constant.
In the equation y = x + 3, y is directly proportional to x.