Question

Tính:

75% - 1 1/2 + 0,5 : 5/12 - (-1/2)²

Answer 1

=3/4-3/2+1/2*12/5-1/4

=1/2-3/2+12/10

=6/5-1=1/5

Answer 2

\(75\%-1\dfrac{1}{2}+0,5:\dfrac{5}{12}-\left(-\dfrac{1}{2}\right)^2\)

\(=\dfrac{3}{4}-\dfrac{3}{2}+\dfrac{1}{2}:\dfrac{5}{12}-\dfrac{1}{4}\)

\(=\dfrac{3}{4}-\dfrac{3}{2}+\dfrac{1}{2}\times\dfrac{12}{5}-\dfrac{1}{4}\)

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

\(=\dfrac{6}{8}-\dfrac{12}{8}+\dfrac{6}{5}-\dfrac{1}{4}\)

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

\(=\left(\dfrac{-3}{4}-\dfrac{1}{4}\right)+\dfrac{6}{5}\)

\(=-1+\dfrac{6}{5}\)

\(=\dfrac{1}{5}\)