1. Stating the problem: We want to find the sum of the integers from 1 to 7. 2. Formula used: The sum of the first $n$ natural numbers is given by the formula $$S = \frac{n(n+1)}{2}$$ where $n$ is the last number in the sequence. 3. Applying the formula: Here, $n=7$, so we substitute into the formula: $$S = \frac{7(7+1)}{2}$$ 4. Simplify inside the parentheses: $$S = \frac{7 \times 8}{2}$$ 5. Multiply numerator: $$S = \frac{56}{2}$$ 6. Simplify the fraction by canceling common factors: $$S = \frac{\cancel{56}}{\cancel{2}} = 28$$ 7. Final answer: The sum of the numbers from 1 to 7 is $28$. Example: Adding 1 + 2 + 3 + 4 + 5 + 6 + 7 step-by-step also equals 28, confirming the formula's correctness.