Question

Найдите значение выражения:
а) (6-8/15)-(4-3 3/20);
б) 4-(41/84-5/21)+7 3/4.

Answer 1

$\displaystyle 1)(6-\frac{8}{15})-(4-3\frac{3}{20})=\frac{82}{15}-(4-\frac{63}{20})=\frac{82}{15}-\frac{17}{20}=\frac{277}{60}=4\frac{37}{60}\\ \\2)4-(4\frac{1}{84}-\frac{5}{21})+7\frac{3}{4}=4-(\frac{337}{84}-\frac{5}{21})+\frac{31}{4}=4-\frac{317}{84}+\frac{31}{4}=\frac{335}{42}=7\frac{41}{42}$