1-(-5)×(-79/7)-5×79/9 简便运算
问题描述:
1-(-5)×(-79/7)-5×79/9 简便运算
答
1-(-5)×(-79/7)-5×79/9
=1-5×79/7-5×79/9
=1-5×79×(1/7+1/9)
=1-395×16/63
=1-6320/63
=-6257/63