Question

$1 frac{2}{5}*2 frac{2}{3}-1 frac{2}{3} *3 frac{1}{2}$

Answer 1

$1frac{2}{5}* 2frac{2}{3}-1frac{2}{3}* 3frac{1}{2}=-2frac{1}{10}$

$1frac{2}{5}* 2frac{2}{3}=frac{7}{5}*frac{8}{3}=frac{7*8}{5*3}=frac{56}{15}=3frac{11}{15}$

$1frac{2}{3}* 3frac{1}{2}=frac{5}{3}*frac{7}{2}=frac{5*7}{3*2}=frac{35}{6}=5frac{5}{6}$

$3frac{11}{15}-5frac{5}{6}=frac{56}{15}-frac{35}{6}=frac{112}{30}-frac{175}{30}=-frac{63}{30}=-2frac{1}{10}$ (Наименьшее общее кратное 15 и 6 равно 30)