(-2 1/6+15)+(12+(-3 8/15))

(-2 1/6+15)+(12+(-3 8/15)) = (-13/6 + 15) + (12 - 23/15)

To simplify the equation, convert the mixed numbers into improper fractions:

(-13/6 + 15) + (12 - 23/15) = (-13/6 + 90/6) + (180/15 - 23/15)

Now, add and subtract the fractions accordingly:

(-13/6 + 90/6) + (180/15 - 23/15) = (77/6) + (157/15)

To add fractions, find a common denominator:

(77/6) + (157/15) = (77/6) * (5/5) + (157/15) * (2/2) = (385/30) + (314/30)

Now, add the numerators:

(385/30) + (314/30) = (385 + 314)/30 = 699/30

Simplify the fraction if possible:

699/30 = 23 9/30 = 23 3/10

So, the answer in Russian is 23 3/10.