6.比较$-\dfrac{17}{2025}$和$-\dfrac{34}{4071}$的大小.

6. 解:$\left\lvert -\dfrac{17}{2025}\right\rvert=\dfrac{17}{2025},\left\lvert -\dfrac{34}{4071}\right\rvert=\dfrac{34}{4071}$.
因为$\dfrac{17}{2025}÷\dfrac{34}{4071}=\dfrac{17}{2025}×\dfrac{4071}{34}=\dfrac{1357}{1350}＞1$,所以$\dfrac{17}{2025}＞\dfrac{34}{4071}$.
所以$-\dfrac{17}{2025}＜-\dfrac{34}{4071}$.

7.比较$-\frac{6}{23}, -\frac{4}{17}, -\frac{3}{11}, -\frac{12}{47}$的大小，用“＜”把它们连接起来。

7. 解:因为$-\dfrac{6}{23}=-\dfrac{12}{46},-\dfrac{4}{17}=-\dfrac{12}{51},-\dfrac{3}{11}=-\dfrac{12}{44},-\dfrac{12}{44}＜-\dfrac{12}{46}＜-\dfrac{12}{47}＜-\dfrac{12}{51}$,
所以$-\dfrac{3}{11}＜-\dfrac{6}{23}＜-\dfrac{12}{47}＜-\dfrac{4}{17}$.