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Now I'm going to show you how to find proportions. Say we have a box and there are ten marbles
and I'm going to draw some of them as colored marbles and some of them as empty marbles.
So, that's a colored marble. So we have six colored marbles and four uncolored marbles.
In total there are ten marbles. If we wanted to write the proportion of the marbles that
are colored, we would write six to ten.
Okay, now the total number of marbles, the total number of marbles is ten. To find the
proportion that are colored, six to ten, that is the normal form of a proportion, six colored
out of ten marbles. If we wanted to find the proportion that are uncolored, we find the
number that are non-colored and also, we also take into account the total number of marbles,
four out of ten. If we want to take into account how many out of the total population comparing
the number of colored marbles to non-colored marbles, we would say the proportion of colored
to non-colored is six to four.
So notice how the proportion of colored to total, non-colored to total and colored to
non-colored are all different proportions. Okay, to express this proportion as a fraction,
let's take the non-colored marbles out of the total marbles in the box, four ten, four
out of ten can be written as four out of ten, which can then be reduced to two fifths. So
the proportion four out of ten can be written as a fraction and then reduced further.