In a classroom , 4 students are wearing red shirts, 11 students are wearing blue shirts, and 10 students are wearing black shirts. What is the ratio...

We are given
that 4 students are wearing red shirts, 11 students are wearing blue shirts, and 10 students are
wearing black shirts. We are asked to find the ratio of students wearing red or black shirts to
the students wearing blue shirts.

A ratio can be written as `a/b` or `a:b` .
A ratio can be thought of as a fraction. Ratios differ from rates in that the units for ratios
must be the same so that the ratio represents a number. (A rate has different units: i.e., miles
per gallon.)

For this ratio the numerator is the number of students wearing
red or black shirts, while the denominator is the number of students wearing blue
shirts.

For the numerator we see the word "or". The number of
students wearing red or black shirts can be found by adding the numbers together. Thus there are
4+10=14 students wearing red or black shirts.

Thus the ratio of
students wearing red or black to the number of students wearing blue is 14:11 or
`14/11` .

(Note that `14/11` considered as a fraction is an improper fraction
and could be written as `1 3/11` ; however as a ratio we do not rewrite in this manner. However,
we typically write rations in simplified or reduced form. Thus `6/4=3/2` or 6:4 is the same as
3:2.)

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