Question: User: 0,5 x 2/7 - 1
1. **Stating the problem:** Calculate the value of the expression $0,5 \times \frac{2}{7} - 1$.
2. **Convert decimal to fraction:** Note that $0,5$ is the same as $\frac{1}{2}$.
3. **Rewrite the expression:** The expression becomes $$\frac{1}{2} \times \frac{2}{7} - 1$$.
4. **Multiply the fractions:** Multiply the numerators and denominators:
$$\frac{1 \times 2}{2 \times 7} = \frac{2}{14}$$.
5. **Simplify the fraction:** Cancel common factors:
$$\frac{\cancel{2}}{7 \times \cancel{2}} = \frac{1}{7}$$.
6. **Substitute back:** The expression is now $$\frac{1}{7} - 1$$.
7. **Rewrite 1 as a fraction:** $$1 = \frac{7}{7}$$.
8. **Subtract the fractions:** $$\frac{1}{7} - \frac{7}{7} = \frac{1 - 7}{7} = \frac{-6}{7}$$.
9. **Final answer:** The value of the expression is $$-\frac{6}{7}$$.