Найдите значение выражения (11/35 – 9/14) ⋅ 21

Источник: Ященко ОГЭ 2025 (36 вар.)

Решение:

(11/35 – 9/14) ⋅ 21 = 11 ⋅ 21 / 35 – 9 ⋅ 21 / 14 = 11 ⋅ 3 / 5 – 9 ⋅ 3 / 2 = 11 ⋅ 3 ⋅ 2 – 9 ⋅ 3 ⋅ 5 / 10 = 66 – 135 / 10 = -69 / 10 = -6,9

Ответ: -6,9