Question

Thực hiện phép tính

1) 6/7 + 5/8 : 5 - 3/16 . ( -2)mũ 2

2) -1/6 + 2/3 . -3/4 + (-2)mũ 2 / 5 chú ý : / là phần nha

3) 2 3/4 . (-0,4 ) + 1 3/5 . 1,75 + (-7,2 ) : 9/11

4) 1/8 . 15 2/5 + 1 4/5 . 7/8 - 17 1/5 . 1/8

Answer 1

1: \(=\dfrac{6}{7}+\dfrac{1}{8}-\dfrac{3}{16}\cdot4=\dfrac{6}{7}+\dfrac{1}{8}-\dfrac{3}{4}\)

\(=\dfrac{48}{56}+\dfrac{7}{56}-\dfrac{42}{56}=\dfrac{13}{56}\)

2: \(=-\dfrac{1}{6}+\dfrac{2}{3}\cdot\dfrac{-3}{4}+\dfrac{4}{5}\)

\(=\dfrac{19}{30}-\dfrac{1}{2}=\dfrac{19}{30}-\dfrac{15}{30}=\dfrac{4}{30}=\dfrac{2}{15}\)

3: \(=\dfrac{11}{4}\cdot\dfrac{-2}{5}+\dfrac{8}{5}\cdot\dfrac{7}{4}+\dfrac{-36}{5}\cdot\dfrac{11}{9}\)

\(=\dfrac{-22+56}{20}+\dfrac{-44}{5}\)

\(=\dfrac{-71}{10}\)