\(a.\frac{2}{3}+\frac{5}{4}=\frac{8}{12}+\frac{15}{12}=\frac{23}{12}\)
\(b.\frac{3}{5}+\frac{9}{8}=\frac{24}{40}+\frac{45}{40}=\frac{69}{40}\)
\(c.\frac{3}{4}-\frac{2}{7}=\frac{21}{28}-\frac{8}{28}=\frac{13}{28}\)
A) 2/3+5/4
= 8/12+15/12
=23/12
B) 3/5+9/8
= 24/40+45/40
=69/40
C)3/4-2/7
= 21/28-8/28
= 13/28
k mink nha mink nhanh nhất
a) 2/3+5/4
=8/12+15/12
=23/12
b)3/5+9/8
=24/40+45/40
=69/40
c)3/4-2/7
=21/28-8/28
=13/28
ok k nhé
\(a,\frac{2}{3}+\frac{5}{4}\)
\(=\frac{8}{12}+\frac{15}{12}\)
\(=\frac{23}{12}\)
\(b,\frac{3}{5}+\frac{9}{8}\)
\(=\frac{24}{40}+\frac{45}{40}\)
\(=\frac{69}{40}\)
\(c,\frac{3}{4}-\frac{2}{7}\)
\(=\frac{21}{28}-\frac{8}{28}\)
\(=\frac{13}{28}\)