Exercise 1 Page 83

There are many different ways to compare amounts or quantities. A ratio is a comparison of two quantities by division. For example, the ratio of a to b can be written in two different ways. a/b or a: b We want to find the ratio of action DVDs to the total number of DVDs Amos owns. We know the number of action DVDs, but we do not know the total number of DVDs. Let's start by calculating the total number of DVDs Amos owns. Action DVDs:& 12 Total DVDs:& 12+15+9= 36 Now we can write the fraction that represents the desired ratio. We will write the number of action DVDs in the numerator and the total number of DVDs in the denominator. l Action DVDs→ Total DVDs→ 12/36 Finally, since the greatest common factor of 12 and 36 is 12, we can reduce the fraction by dividing both the numerator and denominator by 12.

12/36

ReduceFrac

a/b=.a / 12./.b / 12.

12÷ 12/36÷ 12

SimpQuot

Simplify quotient

1/3

FracToScale

\dfrac a b = a:b

1:3

The ratio is 13, 1 to 3, or 1:3. This means that 1 out of every 3 DVD that Amos owns is an action DVD.