Question

\(\frac{2}{7}\)+ \(\frac{5}{14}\)+\(\frac{1}{7}\)+\(\frac{3}{14}\)

\(\frac{1995×1997-1}{1996×1995+1994}\)

469 × 281 + 489 × 719

Giúp mình nha . Mai mình nội bài rồi :((

Answer 1

\(\frac{2}{7}\)+ \(\frac{5}{14}\)+\(\frac{1}{7}\)+ \(\frac{3}{14}\)=\(\frac{4}{14}\)+\(\frac{5}{14}\)+\(\frac{2}{14}\)+\(\frac{3}{14}\)=\(\frac{14}{14}\)=1

469x281+489x719=469x281+(469+20)x719=469x281+469x719+20x719=469x(281+719)+1438=469x1000+1438=469000+1438=470438

Answer 2

a\(\frac{2}{5}\)+\(\frac{5}{14}\)+\(\frac{1}{7}\)+\(\frac{3}{14}\)=\(\frac{53}{70}\)+\(\frac{1}{7}\)=\(\frac{9}{10}\)+\(\frac{3}{14}\)=\(\frac{39}{35}\)

b\(\frac{1995.1997-1}{1996.1995+1994}\)=3984008001

c    469x281+489x719

=(489-469)x(281+719)

=20x1000

=20000

Answer 3

minh rut gon roi nha