Viết 2 giờ 15 phút dưới dạng hỗn số với đơn vị là giờ:

$1\dfrac{2}{3}$ 

\(3\dfrac{1}{3}\)  

\(3\dfrac{1}{4}\)           

\(1\dfrac{1}{3}\)

$ - \dfrac{1}{4}$        

\(\dfrac{3}{2}\)  

\(\dfrac{1}{4}\)                 

\(\dfrac{3}{4}\)

$x = 1$ 

\(x = 2\)  

\(x = 3\)

\(x = 4\)

\(\left( { - 3\dfrac{3}{4}} \right).1\dfrac{1}{2} =  - 3\dfrac{3}{8}\)                       

\(3\dfrac{3}{4}:1\dfrac{1}{5} = 3\dfrac{3}{{20}}\)  

\(\left( { - 3} \right) - \left( { - 2\dfrac{2}{5}} \right) = \dfrac{{ - 3}}{5}\)          

\(5\dfrac{7}{{10}}.15 = \dfrac{{105}}{2}\)

$ - 870$ 

\( - 87\)  

\(870\)

\(92\dfrac{7}{{10}}\)

\(x \in \left\{ {2;3;4;5;6} \right\}\)             

\(x \in \left\{ {3,4;5;6} \right\}\)

\(x \in \left\{ {2;3,4;5} \right\}\)

\(x \in \left\{ {3,4;5;6;7} \right\}\)

\(2\dfrac{1}{3}\); \(4\dfrac{5}{6}\); \(6\dfrac{1}{6}\); \(9\dfrac{1}{2}\)

\(2\dfrac{1}{4}\); \(4\dfrac{1}{6}\); \(6\dfrac{1}{6}\); \(9\dfrac{1}{2}\)

\(2\dfrac{1}{3}\); \(4\dfrac{5}{6}\); \(6\dfrac{5}{6}\); \(9\dfrac{1}{2}\)

\(2\dfrac{1}{3}\); \(4\dfrac{5}{6}\); \(6\dfrac{1}{6}\); \(9\dfrac{1}{6}\)