The initial number of copies, denoted as x, is approximately 2886. Therefore, the discographic initially released 2886 copies of the disc, with 4400 remaining unsold after subsequent reissues and sales.
Let's denote the initial number of copies as x. The discographic initially sold 4/5x copies. After reissuing, the total number of copies became 4/5x + 40000. They then sold 9/10 of this total, leaving 4400 copies unsold.
The equation representing this situation is:
(9/10)(4/5x + 40000) + 4400 = x
Solving this equation will give us the initial number of copies (x). We can simplify the equation and solve for x:
(9/10)(4/5x + 40000) + 4400 = x
(36/50)x + 36000 + 4400 = x
(36/50)x + 40400 = x
36x + 40400 = 50x
14x = 40400
x = 40400/14
x = 2885.71
Since the number of copies must be a whole number, the initial number of copies is approximately 2886. Therefore, there were initially 2886 copies of the disc.
Complete question:
A record company releases several copies of a record. It sells 4/5 of the initial quantity, they sold so many that they reissued 40,000 more copies. After the reissue they sold 9/10 of the sum of the rest of the initial quantity and the new copies. There are 4,400 copies left unsold. How many copies were there at the beginning?