Question

Subtractthe sum of 23 and -5 4 from the difference of 4 and -2 .
7 7 15 5

Answer 1

$$\begin{gathered} \mathrm{The}\mathrm{sum}\mathrm{of}2\frac{3}{7}\mathrm{and}-5\frac{4}{7}\mathrm{is} \\ \left(2\frac{3}{7}\right)+\left(-5\frac{4}{7}\right)=\left(\frac{17}{7}\right)+\left(-\frac{39}{7}\right)=\frac{17}{7}-\frac{39}{7}=\frac{17-39}{7}=-\frac{22}{7} \\ \mathrm{The}\mathrm{difference}\mathrm{of}\frac{4}{15}\mathrm{and}-\frac{2}{5}\mathrm{is} \\ \left(\frac{4}{15}\right)-\left(-\frac{2}{5}\right)=\frac{4}{15}+\frac{2}{5}=\frac{4}{15}+\frac{2\times 3}{5\times 3}=\frac{4}{15}+\frac{6}{15}=\frac{4+6}{15}=\frac{10}{15}=\frac{2}{3} \\ \mathrm{Now},\mathrm{subracting}\mathrm{sum}\mathrm{of}2\frac{3}{7}\mathrm{and}-5\frac{4}{7}\mathrm{from}\mathrm{the}\mathrm{difference}\mathrm{of}\frac{4}{15}\mathrm{and}-\frac{2}{5}\mathrm{is} \\ \mathrm{we}\mathrm{can}\mathrm{write}: \\ \frac{2}{3}-\left(-\frac{22}{7}\right)=\frac{2}{3}+\frac{22}{7}=\frac{2\times 7}{3\times 7}+\frac{22\times 3}{7\times 3}=\frac{14}{21}+\frac{66}{21} \\ =\frac{14+66}{21}=\frac{80}{21}=3\frac{17}{21}. \end{gathered}$$