Đáp án+Giải thích các bước giải:
$a)$ $1,5 : 2,16$ = $150$ : $216$ = $25 : 36$
$b)$ $4\dfrac{2}{7}$ : $\dfrac{3}{5}$ = $\dfrac{30}{7}$ : $\dfrac{3}{5}$ = $\dfrac{30}{7}$ . $\dfrac{5}{3}$ = $\dfrac{150}{21}$ = $\dfrac{50}{7}$
$c)$ $\dfrac{2}{9}$ : $0,31$ = $\dfrac{2}{9}$ : $\dfrac{31}{100}$ = $\dfrac{2}{9}$ . $\dfrac{100}{31}$ = $\dfrac{200}{279}$