Đáp án:
$A<B$
Giải thích các bước giải:
$\begin{array}{l}A=\dfrac{1}{2}+\dfrac{5}{99}+\dfrac{1}{3}+\dfrac{5}{-99}\\=(\dfrac{1}{2}+\dfrac{1}{3})+(\dfrac{5}{99}-\dfrac{5}{99})\\=\dfrac{1}{2}+\dfrac{1}{3}+0\\=\dfrac{2+3}{6}=\dfrac{5}{6}\\+)\dfrac{5}{6}<\dfrac{6}{6}=1(1)\\mà:\dfrac{7}{6}>\dfrac{6}{6}=1(2)\\(1),(2)→\dfrac{5}{6}<\dfrac{7}{6}\\→A<\dfrac{7}{6}\\\underline{\text{CHÚC BẠN HỌC TỐT}}\\\end{array}$
