To solve this equation, we will first simplify the left side by distributing the 8:

(5/8y - 23/4) 8 = 3
(5/8y - 6/4) 8 = 3
(5/8y - 3/2) 8 = 3

Now, we will multiply both sides by the reciprocal of 8 (which is 1/8) to isolate y:

(5/8y - 3/2) 8 1/8 = 3 * 1/8
5y - 24 = 3/8

Now, we will add 24 to both sides to get y by itself:

5y - 24 + 24 = 3/8 + 24
5y = 3/8 + 24
5y = 3/8 + 192/8
5y = 195/8

Finally, we will divide by 5 to solve for y:

y = (195/8) / 5
y = 195/40
y = 39/8

Therefore, the solution to the equation is y = 39/8.