(5432 + 8951) + (4568 + a + 1049) = 5432 + 8951 + (4568 + a + 1049) = 5432 + 8951 + 4568 + a + 1049 = 20000 + a
(5432 + 8951) + (4568 + a + 1049) = 5432 + 8951 + (4568 + a + 1049) = 5432 + 8951 + 4568 + a + 1049 = 20000 + a