Question

Tính thuận tiện:

1978 x 1979 + 1980 x 24 + 1985 / 1980 x 1979 - 1978 x 1979

Answer 1

\(\dfrac{1978\times1979+1980\times24}{1980\times1979-1978\times1979}\)

\(=\dfrac{24+1985}{1979}\)

\(=\dfrac{24+\left(6+1979\right)}{1979}\)

\(=24+6=30\)

Answer 2

$\text{$\dfrac{1978  \text{x}  1979 + 1980  \text{x}   24 + 1985}{1980  \text{x}  1979 - 1978  \text{x}  1979}$}$

 

$\text{$\dfrac{24 + 1985}{1979}$}$

 

$\text{$\dfrac{24 + (6 + 1979)}{1979}$}$

 

$\text{24 + 6}$

 

$\text{30}$

`@` `color[Green][Nhi]`