Rational Numbers What are they

Rational Number What are they?

Rational Numbers

​1.5 is a rational number because

1.5 = 3/2 (3 and 2 are both integers)

Rational Number

There is no 0 in the denominator

Most numbers we use in everyday life are

Rational Numbers.

1/4 = 0.25
12/4 = 3

-12/4 = -3

Examples of Rational Numbers

​Number	​Fraction	​Rational?
​5	​5/1	​yes
1.75​	​7/4	​yes
1000​	​1000/1	yes​
​.001	​1/1000	yes​
​-0.1	​-1/10	yes​

​A rational number is a number that can be in the form p/q where p and q are integers and q is not equal to zero.

Multiple Choice

Which of the following is NOT a Rational Number?

• 1/2

• 5/3

• -10/2

• 7/0

Multiplying Rational Numbers

​Remember: p/q are rational numbers (no zero for q)

Multiple Choice

Is the following equation a correct way to multiply Rational Numbers? $$\frac{1}{2}\times\frac{3}{1}=\frac{1\times1}{2\times3}=\frac{1}{6}$$

• yes

• no, why