Answer:
Why might he think that and what would you tell him?
He thought perhaps that numbers were formed by rational numbers of the form [tex]\frac{1}{x}[/tex], where [tex]x\in \mathbb{N}[/tex]. I would tell him that there are rational numbers [tex]\frac{y}{z}[/tex], such that [tex]\frac{1}{x}\le \frac{y}{z} \le \frac{1}{x+1}[/tex], where [tex]x[/tex], [tex]y[/tex], [tex]z \in \mathbb{N}[/tex].
Is there a number that falls between these?
[tex]\frac{7}{24}[/tex] is a rational number between [tex]\frac{1}{3}[/tex] and [tex]\frac{1}{4}[/tex].
Step-by-step explanation:
Why might he think that and what would you tell him?
He thought perhaps that numbers were formed by rational numbers of the form [tex]\frac{1}{x}[/tex], where [tex]x\in \mathbb{N}[/tex]. I would tell him that there are rational numbers [tex]\frac{y}{z}[/tex], such that [tex]\frac{1}{x}\le \frac{y}{z} \le \frac{1}{x+1}[/tex], where [tex]x[/tex], [tex]y[/tex], [tex]z \in \mathbb{N}[/tex].
Is there a number that falls between these?
Indeed, the average number of [tex]\frac{1}{3}[/tex] and [tex]\frac{1}{4}[/tex], for instance. That is:
[tex]\frac{y}{z} = \frac{\frac{1}{3}+\frac{1}{4} }{2}[/tex]
[tex]\frac{y}{z} = \frac{\frac{7}{12} }{2}[/tex]
[tex]\frac{y}{z} = \frac{7}{24}[/tex]
[tex]\frac{7}{24}[/tex] is a rational number between [tex]\frac{1}{3}[/tex] and [tex]\frac{1}{4}[/tex].