Question

甲、乙、丙三個(gè)數(shù)依次小1，已知乙數(shù)的倒數(shù)與甲數(shù)的倒數(shù)的2倍之和與丙的倒數(shù)的3倍相等，設(shè)甲數(shù)為x，則所列方程為

 

．

Answer 1

分析：設(shè)甲數(shù)為x，則乙丙分別為x-1，x-2，根據(jù)乙數(shù)的倒數(shù)與甲數(shù)的倒數(shù)的2倍之和與丙的倒數(shù)的3倍相等，列出方程．

解答：解：設(shè)甲數(shù)為x，則乙丙分別為x-1，x-2，
由題意得，

1

x-1

+2×

1

x

=3×

1

x-2

．
故答案為：

1

x-1

+2×

1

x

=3×

1

x-2

．

點(diǎn)評(píng)：本題考查了由實(shí)際問(wèn)題抽象出分式方程，解答本題的關(guān)鍵是分別表示出甲乙丙的倒數(shù)，根據(jù)等量關(guān)系列出分式方程．