Вычислите: 81/88 * (6 целых - 1целая 13/15 * 1целую 19/21)

/ - это дробь

[tex] \frac{81}{88}*(6 -1\frac{13}{15} *1 \frac{19}{21})=\frac{81}{88}*(6 -\frac{28}{15} *\frac{40}{21})= \frac{81}{88}*( \frac{6}{1} -\frac{4}{3} *\frac{8}{3})= [/tex][tex] \frac{81}{88}*( \frac{6}{1} -\frac{32}{9})= \frac{81}{88}*( \frac{54}{9} - \frac{32}{9} )= \frac{81}{88} * \frac{22}{9} = \frac{9}{4} * \frac{1}{1} =2\frac{1}{4} =2,25[/tex]

[tex] \frac{81}{88} (6-1 \frac{13}{15} *1 \frac{19}{21} )= \frac{81}{88}(6- \frac{28}{15} * \frac{40}{21})= \frac{81}{88} (6- \frac{4}{3}* \frac{8}{3} )= \frac{81}{88} (6- \frac{32}{9})=[/tex]
[tex] \frac{81}{88} ( \frac{54}{9} - \frac{32}{9} )= \frac{81}{88} * \frac{22}{9}= \frac{9}{4} [/tex]

Ответ: [tex] \frac{9}{4} [/tex] или [tex]2 \frac{1}{4} [/tex] или 2.25