Решите уравнение (2/15 + у) - 7/30 = 1/10
(2/15 +y) - 7/30 =1/10 (4/30 +y) - 7/30 =3/30 4/30 +y = 10/30 y = 10/30 - 4/30 y = 6/30 = 1/5