Question

Выполните действия:
1) 2 1/2•(2/15-3 5/6)+1/4

Answer 1

$2 frac{1}{2} cdot(frac{2}{15}-3frac{5}{6})+frac{1}{4}= frac{5}{2} cdot(frac{2}{15}-frac{23}{6})+frac{1}{4}= \ \ = frac{5}{2} cdot(frac{4}{30}-frac{115}{30})+frac{1}{4}= \ \ = frac{5}{2} cdot(-frac{111}{30})+frac{15}{60}= -frac{555}{60}+frac{15}{60}=-frac{540}{60}=-9$