What is the equivalent of (- 5 / 6 of 2000) + (- 1 / 2 of 1999) + 3 / 4 of 4000 + (- 1 / 2)

What is the equivalent of (- 5 / 6 of 2000) + (- 1 / 2 of 1999) + 3 / 4 of 4000 + (- 1 / 2)

2:6 5-2:5 2 + 4:6 1-3:5 3% d% a = (2:6 5 + 4:6 1) - (2:5 2 + 3:5 3)% d% a = 7-6% d% a = 1% d% a