\(A=\frac{3}{4}+\frac{2}{7}+\frac{1}{4}+\frac{3}{5}+\frac{5}{7}\)
\(A=\left(\frac{3}{4}+\frac{1}{4}\right)+\left(\frac{2}{7}+\frac{5}{7}\right)+\frac{3}{5}\)
\(A=1+1+\frac{3}{5}\)
\(A=\frac{5}{5}+\frac{5}{5}+\frac{3}{5}\)
\(A=\frac{13}{5}\)
A=(3/4+1/4)+(2/+5/7)+3/5
A= 1+1+3/5
A=13/5
A = ( 3/4 + 1/4 ) + ( 2/7 + 5/7 ) + 3/5
A = 5/4 + 1 + 3/5
A = 25/20 + 1 + 12/20
A = 37/20 + 1
A = 1 và 37/20
= ( 3/4 + 1/4 ) + ( 2/7 + 5/7 ) + 3/5
= 1 + 1 + 3/5
= 2 + 3/5
=1
