1) 1/3 a + 5/6 a - 1/2 a,якщо а=1/4,3/8,9/16,15/22

1) 1/3а+5/6а-1/2=1/3*1/4+5/6*1/4-1/2=1/12+5/24-1/2=2/24+5/24-12/24=5/24;   2)1/3*3/8+5/6*3/8-1/2=3/24+15/48-1/2=6/48+15/48-24/48=-3/48=-1/16;           3)1/3*9/16+5/6*9/16-1/2=9/48+45/96-1/2=3/16+15/32-16/32=6/32-1/32=5/32;   4)1/3*15/22+5/6*15/22-1/2=15/66+75/132-1/2=5/22+25/44-22/44=10/44+3/44=13/44.