Вычислите (это дроби)

(1/2-1/3) : (1/13-1/14) * (1/14-1/15) : (1/15-1/16) = ?

Решить резвернуто

И второй

(1/14-1/15) : (1/15-1/16) * (1/16-1/17) : (1/17-1/18) = ?

Тоже развернуто решить

Я в пятом классе

1) (1/2-1/3) : (1/13-1/14) * (1/14-1/15) : (1/15-1/16) =

(3 / (2*3) - 2 / (2*3)) : (14 / (13*14) - 13 / (13*14)) * (15 / (14*15) - 14 / (14*15)) : (16 / (15*16) - 15 / (15*16)) = (1/6) : (1 / (13*14)) * (1 / (14*15)) : (1 / (15*16)) = ((13*14) / 6) * ((15*16) / 14*15) =

((13*14) / 6) * 16/14 = (13*14*16) / (6*14) = (13*16) / 6 = (13*8) / 3 = 104/3 = 34 2/3;

2) (1/14-1/15) : (1/15-1/16) * (1/16-1/17) : (1/17-1/18) =

(15 / (14*15) - 14 / (14*15)) : (16 / (15*16) - 15 / (15*16)) * (17 / (16*17) - 16 / (16*17)) : (18 / (17*18) - 17 / (17*18)) =

(1 / (14*15)) : (1 / (15*16)) * (1 / (15*16)) : (1 / (16*17)) = ((15*16) / (14*15)) * ((16*17) / (15*16)) = (16/14) * (17/15) = (16*17) / (14*15) = (8*17) / (7*15) = 136/105 = 1 31/105;