среднее арифметическое 3-х чисел одинаково 2 целым и 3/5 1-ое число

Пусть a,b,c -- разыскиваемые числа. Тогда:

(a + b + c)/3 = 2 3/5
a = b : 1 1/2
b = c - 1 2/5

(a + b + c)/3 = 13/5
a = b : 3/2
b = c - 7/5

a + b + c = 39/5
a = b * 2/3
b = c - 7/5

с = b + 7/5
a = 2b/3
2b/3 + b + b + 7/5 = 39/5

c = b + 7/5
c = 2b/3
10b/15 + 30b/15 + 21/15 = 117/15

40b/15 = 96/15
a = 2b/3
c = b + 7/5

b = 96/40 = 12/5
c = 12/5 + 7/5 = 19/5
a = 12/5 *2/3 = 8/5

Ответ: 8/5; 12/5; 19/5.