Question

Answer 1

Bài 1:

a: \(1\dfrac{3}{4}-0,25=\dfrac{7}{4}-\dfrac{1}{4}=\dfrac{6}{4}=\dfrac{3}{2}\)

b: \(15\dfrac{2}{3}:\left(-\dfrac{1}{3}\right)+\sqrt{25}=\dfrac{47}{3}\cdot\dfrac{3}{-1}+5=-47+5=-42\)

Bài 2:

a: \(4:15=x:3\)

=>\(\dfrac{x}{3}=\dfrac{4}{15}\)

=>\(x=\dfrac{4}{15}\cdot3=\dfrac{12}{15}=\dfrac{4}{5}\)

b: \(\dfrac{1}{3}-3x=\left(-\dfrac{2}{3}\right)^2\)

=>\(\dfrac{1}{3}-3x=\dfrac{4}{9}\)

=>\(3x=\dfrac{1}{3}-\dfrac{4}{9}=-\dfrac{1}{9}\)

=>\(x=-\dfrac{1}{9}:3=-\dfrac{1}{27}\)