计算： (1) $87 \times \left(-\frac{5}{29} - \frac{2}{3}\right)$; (2) $(-60) \times \left(\frac{1}{2} - \frac{2}{3} - \frac{4}{5}\right)$. 计算： (1) $(-2) \times 17 \times (-5)$; (2) $(-15) \times (-3) \times (-4) \times 2$. 直接判断下列各式计算结果的符号： (1) $(-2) \times 7 \times 8$; (2) $(-3) \times 5 \times \left(-\frac{6}{7}\right)$; (3) $\frac{1}{4} \times (-2.1) \times (-6) \times (-3)$; (4) $(-3.6) \times (-5) \times (-4) \times \left(-\frac{3}{11}\right)$; (5) $4 \times (-8.1) \times (-11) \times (-14) \times \left(-\frac{2}{9}\right) \times \left(-\frac{6}{11}\right)$. 计算： (1) $\left(-\frac{1}{4}\right) \times 7 \times 4$; (2) $(-0.125) \times 9 \times (-8)$; (3) $(-1.5) \times (-6) \times (-4)$; (4) $\left(-\frac{1}{4}\right) \times \left(-\frac{1}{5}\right) \times \left(-\frac{1}{7}\right) \times (-20)$.
计算： (1) $87 \times \left(-\frac{5}{29} - \frac{2}{3}\right)$; (2) $(-60) \times \left(\frac{1}{2} - \frac{2}{3} - \frac{4}{5}\right)$. 计算： (1) $(-2) \times 17 \times (-5)$; (2) $(-15) \times (-3) \times (-4) \times 2$. 直接判断下列各式计算结果的符号： (1) $(-2) \times 7 \times 8$; (2) $(-3) \times 5 \times \left(-\frac{6}{7}\right)$; (3) $\frac{1}{4} \times (-2.1) \times (-6) \times (-3)$; (4) $(-3.6) \times (-5) \times (-4) \times \left(-\frac{3}{11}\right)$; (5) $4 \times (-8.1) \times (-11) \times (-14) \times \left(-\frac{2}{9}\right) \times \left(-\frac{6}{11}\right)$. 计算： (1) $\left(-\frac{1}{4}\right) \times 7 \times 4$; (2) $(-0.125) \times 9 \times (-8)$; (3) $(-1.5) \times (-6) \times (-4)$; (4) $\left(-\frac{1}{4}\right) \times \left(-\frac{1}{5}\right) \times \left(-\frac{1}{7}\right) \times (-20)$.
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