A rational number can be written as a fraction. It can be written either as a proper fraction (`frac(1)(3)`) where the denominator is larger than the numerator; or as an improper fraction (`frac(12)(5)`).
(Higher Students: recurring decimals can be written as a fraction, and are therefore rational)
An irrational number cannot be written as a fraction. Examples of irrational numbers include π and √2.
Is (π ÷ 4) a rational number?
Answer: No, because π is not a rational number.
Is `-sqrt(0.25)` a rational number?
`-sqrt(0.25)`
`= -(0.5)`
`= -frac(1)(2)`
Because it can be written as a fraction, it is a rational number.
Answer: Yes, because it can be written as `-frac(1)(2)`