1.
a)
[tex]1 \frac{3}{7} = \frac{10}{7} [/tex]
b)
[tex]3 \frac{1}{5} = \frac{16}{5} [/tex]
c)
[tex] \frac{19}{8} = 2 \frac{3}{8} [/tex]
d)
[tex] \frac{26}{7} = 3 \frac{5}{7} [/tex]
2.
a)
[tex] \frac{21}{24} = \frac{7}{8} [/tex]
b)
[tex] \frac{84}{9} = 9 \frac{3}{9} = 9 \frac{1}{3} [/tex]
3.
[tex]4 \frac{1}{5} - \frac{4}{5} + 2 \frac{2}{5} = 6 \frac{3}{5} - \frac{4}{5} = 5 \frac{8}{5} - \frac{4}{5} = \boxed{ 5 \frac{4}{5} kg}[/tex]