左边式子先算除法,再算乘法,最后算加法;
中间式子先算乘法,再按从左到右的顺序算加法;
右边式子先同时算乘法和除法,再算加法。
$\begin{aligned}&\frac{13}{14}÷\frac{15}{28}×\frac{5}{8}+\frac{1}{4}\\=&\frac{13}{14}×\frac{28}{15}×\frac{5}{8}+\frac{1}{4}\\=&\frac{26}{15}×\frac{5}{8}+\frac{1}{4}\\=&\frac{13}{12}+\frac{1}{4}=\frac{4}{3}\end{aligned}$
$\begin{aligned}&\frac{2}{3}+\frac{5}{9}×\frac{3}{2}+\frac{3}{2}\\=&\frac{2}{3}+\frac{5}{6}+\frac{3}{2}\\=&\frac{3}{2}+\frac{3}{2}\\=&3\end{aligned}$
$\begin{aligned}&3.2×1.5+4.8÷2.5\\=&4.8+1.92\\=&6.72\end{aligned}$