Giải bài 3 trang 132 - SGK Toán lớp 4

Tìm $x$:

a) $x + \dfrac{4}{5}=\dfrac{3}{2}\\x\,\,\,\,\,\,\,\,\,\,\,= \dfrac{3}{2} -\dfrac{4}{5}\\x\,\,\,\,\,\,\,\,\,\,\,=\dfrac{7}{10}$         

b) $x - \dfrac{3}{2}=\dfrac{11}{4}\\x\,\,\,\,\,\,\,\,\,\,\,=\dfrac{11}{4}+\dfrac{3}{2}\\x \,\,\,\,\,\,\,\,\,\,\,=\dfrac{34}{8}=\dfrac{17}{4}$             

c)$\dfrac{25}{3} - x = \dfrac{5}{6}\\\,\,\,\,\,\,\,\,\,\,\,\,x =\dfrac{25}{3} - \dfrac{5}{6}\\\,\,\,\,\,\,\,\,\,\,\,\,x =\dfrac{45}{6}=\dfrac{15}{2}$