a)
$\frac{10}{25}$ = $\frac{2}{5}$ = 0,4
$\frac{3}{15}$ = $\frac{1}{5}$ = 0,2
$\frac{14}{2000}$ = $\frac{7}{1000}$ = 0,007
b)
7$\frac{2}{7}$ = $\frac{7 . 7 + 2}{7}$ = $\frac{51}{7}$
6$\frac{3}{5}$ = $\frac{6 . 5 + 3}{5}$ = $\frac{33}{5}$
3$\frac{1}{10}$ = $\frac{3 . 10 + 1}{10}$ = $\frac{31}{10}$
c)
$\frac{23}{5}$ = 4$\frac{3}{5}$ (vì 23 : 5 = 4, dư 3)
$\frac{23}{7}$ = 3$\frac{2}{7}$ (vì 23 : 7 = 3, dư 2)
$\frac{37}{6}$ = 6$\frac{1}{6}$ (vì 37 : 6 = 6, dư 1)