Помогите с 4 по 6 пример сократить

4) $\frac{8*3+8*23}{3*16} = \frac{8*(3+23)}{3*16} = \frac{8*26}{3*16} = \frac{26}{3*2} = \frac{13}{3} =4 \frac{1}{3}$
5) $\frac{17*48}{17*16-9*16}$ = $\frac{17*48}{16*(17-9)} = \frac{17*48}{16*8} = \frac{17*6}{16} = \frac{17*3}{8} = \frac{51}{8} = 6 \frac{3}{8} =6,375$
6) $\frac{14*5-14*3}{21*9+21*3} = \frac{14*(5-3)}{21*(9+3)} = \frac{14*2}{21*12} = \frac{2}{3*6} = \frac{1}{3*3} = \frac{1}{9}$