7/20* 15/17
16/15: 8/25
(3/4)в третьей степени*(4/3)в 3 степени
51/21: (8/25+9/20)- 64/35* 5/4
(1/13+1/14) во 2 степени : (1/13 - 1/14)во 2 степени * (1/27)в 3 степени
1) 7/20*15/17 = 15/20*7/17 = 3/4*7/17 = 21/68 2) 16/15 : 8/25 = 16/15*25/8 = 16/8*25/15 = 2*5/3 = 10/3 3) (3/4)^3*(4/3)^3 = (3/4*4/3)^3 = 1^3 = 1 4) 51/21:(8/25+9/20) - 64/35*5/4 = 17/7:(32+45)/100 - 64/4*5/35 = = 17/7:77/100 - 16*1/7 = 17/7*100/77 - 16/7 = (1700 - 16*77)/(7*77) = = (1700 - 1232)/539 = 468/539 Наверное, тут какая-то опечатка, больно сложная дробь получилась. 5) (1/13+1/14)^2 : (1/13-1/14)^2 * (1/27)^3 = = (14+13)^2/(13*14)^2 : (14-13)^2/(13*14)^2 * 1/27^3 = = 27^2/(13*14)^2 * (13*14)^2/1 * 1/27^3 = 27^2/27^3 = 1/27