a) $\frac{162}{10}$ = $16\frac{2}{10}$ = 16,2 ;          $\frac{975}{10}$ = $97\frac{5}{10}$ = 97,5.

b) $\frac{7409}{100}$ = $74\frac{9}{100}$ = 74,09 ;          $\frac{806}{100}$ = $8\frac{6}{100}$ = 8,06.