Chap 13
DIRECT AND INVERSE PROPORTION
SOME IMPORTANT FACTS
1. If two
quantities increase or decreases together in such a manner that the ratio of
their corresponding values remain constant, we say that the two quantities are
in direct proportion. In other words, x and y are said to vary directly,
if x/y = k, where k is positive
constant.
2. Two
quantities x and y are said to very inversely or indirectly, if an increase in
x causes a decrease in y and a decrease in x causes an increase in y in such a
way that xy remains constant. In other words, x and y are said to be very
indirectly, if xy =k, where k is a positive constant.
