Question

1/2-1/7-1/4 дробь 2 5/14-1 8/21-1/3

Answer 1

1/2-1/7-1/4=(1*14-1*4-1*7)/28=3/28
5/14-18/21-1/3=(3*5-18*2-14*1)/42=-21/42=-1/2