13.15 - (5 and 1 / 8-6 and 17 / 20) - 4.875

13.15 - (5 and 1 / 8-6 and 17 / 20) - 4.875

13.15 - (5 and 1 / 8-6 and 17 / 20) - 4.875
=13.15-5 and 1 / 8 + 6.85-4 and 7 / 8
=(13.15 + 6.85) - (5 and 1 / 8 + 4 and 7 / 8)
=20-10
=10

In short, "half + five sixths - (this is the minus sign) seven twelfth + nine twentieth - eleven thirtieth + thirteen forty-two - fifteen fifty-six."
(I don't know how to score. I can only send it as a sample

The original formula = 1 / 2 + (1 / 2 + 1 / 3) - (1 / 3 + 1 / 4) + (1 / 4 + 1 / 5) - (1 / 5 + 1 / 6) + (1 / 6 + 1 / 7) - (1 / 7 + 1 / 8) = 1 / 2 + 1 / 2 + 1 / 3-1 / 3-1 / 4 + 1 / 5-1 / 5-1 / 6 + 1 / 6 + 1 / 7-1 / 7-1 / 8 = 7 / 8