Question 310944
{{{(8/9)(5/9)-1/7=40/81-1/7}}}
Get a common denominator,
{{{(8/9)(5/9)-1/7=(40/81)(7/7)-(1/7)(81/81)}}}
{{{(8/9)(5/9)-1/7=(280/567)-(81/567)}}}
{{{(8/9)(5/9)-1/7=199/567}}}