Вправи 301 - 400 » 336

Знайдіть значення виразу: 1) 13/22 ∙ 214/15 – (15/8 + 21/8 ∙ 11/17) ∙ 3/7 = 25/22 ∙ 44/15 – (15/8 + 17/8 ∙ 11/17) ∙ 3/7 = 5/1 ∙ 2/3 – (15/8 + 11/8) ∙ 3/7 = 10/3 – (15/8 + 13/8) ∙ 3/7 = 31/3 – 3 ∙ 3/7 = 31/3 – 9/7 = 10/3 – 9/7 = (10 • 7 - 9 • 3)/21 = 43/21 = 21/21; 2) 62/5 ∙ 19/16 – (21/2)2 = 32/5 ∙ 25/16 – 9/4 ∙ 9/4 = 32/1 ∙ 5/16 – 81/16 = (160 - 81)/16 = 79/16 = 415/15.