Question

Find the difference:
$2\frac{7}{9}-1\frac{8}{15}$

Answer 1

$$\begin{gathered} 2\frac{7}{9}-1\frac{8}{15} \\ =\frac{25}{9}-\frac{23}{15} \\ 3\underline{\overline{)9,15}} \\ \underline{3\underline{\overline{)3,5}}} \\ 5\overline{)\underline{1,5}} \\ \overline{)\underline{1,1}} \\ \mathrm{L}.\mathrm{C}.\mathrm{M}.\mathrm{of}9\mathrm{and}15=(3\times 3\times 5)=45 \\ \therefore \frac{25}{9}-\frac{23}{15}=\frac{\left(125-69\right)}{45}=\frac{56}{45}=1\frac{11}{45}\left\{\left[45÷9=5,5\times 25=125\right]\mathrm{and}\left[45÷15=3,3\times 23=69\right]\right\} \end{gathered}$$