Question

Giúp mình với mình sắp phải nộp rùi!

Answer 1

Có: \(3+\dfrac{3}{5}+\dfrac{3}{25}+\dfrac{3}{125}+\dfrac{3}{625}\)
\(=625.\dfrac{3}{625}+125.\dfrac{3}{625}+25.\dfrac{3}{625}+5.\dfrac{3}{625}+1.\dfrac{3}{625}\)
\(=\dfrac{3}{625}.\left(625+125+25+5+1\right)\)
\(=\dfrac{3}{625}.781\)
\(=\dfrac{2343}{625}\)
\(=3,7488\)

Answer 2

\(=625\times\dfrac{3}{625}+125\times\dfrac{3}{625}+5\times\dfrac{3}{625}+1\times\dfrac{3}{625}\) 

\(=\left(625+125+25+5+1\right)\times\dfrac{3}{625}\) 

\(=781\times\dfrac{3}{625}\) 

\(=\dfrac{2343}{625}\)