\(2,5-\dfrac{4}{5}+\dfrac{7}{2}=2,5-0,8+3,5=5,2\)
Lời giải:
$2,5-\frac{4}{5}+\frac{7}{2}=\frac{5}{2}-\frac{4}{5}+\frac{7}{2}$
$=\frac{5+7}{2}-\frac{4}{5}=6-\frac{4}{5}=\frac{30-4}{5}=\frac{26}{5}$
=25/10 - 4/5 + 7/2
=25/10 - 8/10 + 35/10
=17/10 + 35/10
=52/10 = 5,2
Chúc cậu học tốt![]()
\(2.5-\dfrac{4}{5}+\dfrac{7}{2}\\ =2.5-0.8+3.5\\ =5.2\)