Answer:
[tex]5v - \frac{4}{10} = \frac{4}{5} \\ 5v = \frac{4}{5} + \frac{4}{10} \\ 5v = \frac{4}{5} \times \frac{2}{2} + \frac{4}{10} \\ 5v = \frac{8}{10} + \frac{4}{10} \\ 5v = \frac{8 + 4}{10} \\ 5v = \frac{12}{10} \\ 5v = \frac{6}{5} \\ v = \frac{6 }{5 \times 5} = \frac{6}{25} \\ thank \: you[/tex]
