數與數線(2)
Author: 藍邦偉　老師

$∵ \frac{13}{99}<0.1\overline{a2} <\frac{14}{99}⇒\frac{13}{99}<\frac{100+10a+1}{990}<\frac{14}{99}$

⇒130<101+10a<140⇒29<10a<39

⇒2.9<a<3.9⇒a=3

n = 0 (slider from 0 to 3, step 1)