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1 [2025 四川绵阳期中,中]计算:$-16-(-21)+(-12)-35-(-3).$
答案
$-16-(-21)+(-12)-35-(-3) = -16+21-12-35+3 = -(16+12+35)+(21+3) = -39$.
2[2025山东东营质检,中]计算：$(-\dfrac{3}{2})+(-\dfrac{5}{12})+\dfrac{5}{2}+(-\dfrac{7}{12})$
答案
原式$=[(-\dfrac{3}{2})+\dfrac{5}{2}]+[(-\dfrac{5}{12})+(-\dfrac{7}{12})] = 1+(-1) = 0$.
3[2026浙江杭州期末,中]计算：$(-\dfrac{1}{2}) - (-0.25) + (-\dfrac{1}{8}) - \dfrac{7}{8} - (+\dfrac{3}{4})$
答案
原式$=(-\dfrac{1}{2}+\dfrac{1}{4}-\dfrac{3}{4})+(-\dfrac{1}{8}-\dfrac{7}{8}) = -1-1 = -2$.
4[中]计算:$(-1.25)×\frac{5}{7}×(-4)×(-\frac{7}{5}).$
答案
原式$=[(-1.25)×(-4)]×[\dfrac{5}{7}×(-\dfrac{7}{5})] = 5×(-1) = -5$.
5[中]计算：$45×(-25)×\frac{7}{8}×(-\frac{11}{15})÷\frac{1}{4}×(-1\frac{1}{7})$
答案
原式$=-(45×\dfrac{11}{15})×(25×4)×(\dfrac{7}{8}×\dfrac{8}{7}) = -33×100×1 = -3300$.
6[中]计算：$4×(-3\frac{6}{7})-3×(-3\frac{6}{7})-6×3\frac{6}{7}$
答案
原式$=-\dfrac{27}{7}×(4-3+6) = -\dfrac{27}{7}×7 = -27$.
7[中]计算:$1-3×2+5+7-9×2+11+13-15×2+17+···+2011-2013×2+2015+2017.$
答案
原式$=(1-3×2+5)+(7-9×2+11)+(13-15×2+17)+\dots+(2011-2013×2+2015)+2017 = 2017$.
