\(\frac{399\cdot45+55\cdot399}{1995\cdot1996-1991\cdot1995}\)
\(=\frac{399\cdot(45+55)}{1995\cdot(1996-1991)}=\frac{399\cdot100}{1995\cdot5}=\frac{1\cdot20}{5\cdot1}=\frac{20}{5}=4\)
Trả lời
399.45+55.399/1995.1996-1991.1995
=399.(45+55)/1995.(1996-1991)
=399.20.5/399.5.5
=20/5
=4/1=4.
Hok chắc !
\(\frac{399\times45+55\times399}{1995\times1996-1991\times1995}\)
\(=\frac{399\left(45+55\right)}{1995\left(1996-1991\right)}=\frac{100}{5.5}=4\)
#)Giải :
\(\frac{399\times45+55\times399}{1995\times1996-1991\times1995}=\frac{399\times\left(45+55\right)}{1995\times\left(1996-1991\right)}\)
\(=\frac{399\times100}{1995\times5}=\frac{399\times20}{1995}=\frac{399\times4}{399}=4\)
\(\frac{399\times45+55\times399}{1995\times1996-1991\times1995}\)
\(=\frac{399\times\left(45+55\right)}{1995\times1996-1991}\)
\(=\frac{399\times100}{1995\times5}\)
\(=\frac{399\times4\times5\times5}{399\times5\times5}\)
\(=\frac{4}{1}=4\)