Cho \(\frac{a+b+c-d}{d}=\frac{b+c+d-a}{a}=\frac{c+d+a-b}{b}=\frac{d+a+b-d}{c}\)(với đk a+b+c+d khác 0) . Tính giá trị bthuc:

\(P=\left(1+\frac{b+c}{a}\right).\left(1+\frac{c+d}{b}\right).\left(1+\frac{d+a}{c}\right).\left(1+\frac{a+b}{d}\right)\)

Tính = cák hợp lý:

a) \(139\frac{5}{7}:\frac{2}{3}-138\frac{2}{7}:\sqrt{\frac{4}{9}}\)

b) \(\left(\frac{-5}{11}:\frac{13}{18}-\frac{5}{11}:\frac{13}{5}\right)+\frac{-1}{33}\)

c) \(\left|97\frac{2}{3}-125\frac{3}{5}\right|+97\frac{2}{5}-125\frac{1}{3}\)