Question

What percentage of number between 1 and 70 have 1 and 9 in their unit places

Answer 1

HI,
$$\begin{gathered} \mathrm{Number}\mathrm{of}\mathrm{numbers}\mathrm{between}1\mathrm{to}70=70 \\ \mathrm{and}\mathrm{numbers}\mathrm{having}1\mathrm{and}9\mathrm{at}\mathrm{their}\mathrm{unit}\mathrm{place} \\ =1,11,21,31,41,51,61\mathrm{and}9,19,29,39,49,59,69\left\{\mathrm{including}1\right\} \\ =14\mathrm{numbers} \\ \mathrm{so}\%=\frac{14}{70}\times 100=20\% \end{gathered}$$


Regards