(75+91):2=166:2=83
Ответ будет 83
20-8+17-8=29...................
5-(7х+1) = -6х-3
5-7х-1 = -6х-3
-7х+6х = -3-5+1
-х = -7
х = 7
477 - 6; 7;5; 9;8; 7.
478 - 7; 12;14; 13;9; 8.
481 -12/7; 8/5;19/10; 19/15;19/12; 21/13
482 - 18/7; 27/8; 14/5; 34/9; 20/7; 37/11
483 - 43/12; 69/16; 101/20; 43/13; 76/17; 72/14
484 - 50/19; 74/21; 239/30; 114/25; 137/24; 103/15.