1. **Problem statement:** Calculate the sum of the sequence of points given: 15, 14, 13, 12, 11, 10, 9, 8, 7, 6, 5, 4, 3, 2, 1, 0, with the operations +1, +2, -3, -4, -5, -6 applied as indicated. 2. **Understanding the sequence and operations:** The points decrease from 15 down to 0 by 1 each step. The operations +1, +2, -3, -4, -5, -6 are added or subtracted at certain points as shown. 3. **Sum the points first:** The sum of integers from 0 to 15 is given by the formula for the sum of an arithmetic series: $$\text{Sum} = \frac{n(n+1)}{2}$$ where $n=15$. 4. Calculate the sum: $$\text{Sum} = \frac{15 \times (15+1)}{2} = \frac{15 \times 16}{2} = \frac{240}{2} = 120$$ 5. **Sum the operations:** The operations are +1, +2, -3, -4, -5, -6. Calculate their sum: $$1 + 2 - 3 - 4 - 5 - 6 = (1 + 2) - (3 + 4 + 5 + 6) = 3 - 18 = -15$$ 6. **Combine the sums:** Add the sum of points and the sum of operations: $$120 + (-15) = 105$$ 7. **Final answer:** The total sum after applying the operations is **105**.