A = [tex] \frac{2}{5} + \frac{1}{3} : \frac{3}{10} - \frac{1}{2} [/tex]
= [tex] \frac{6}{15} + \frac{5}{15} : \frac{3}{10} - \frac{5}{10} [/tex]
= [tex] \frac{11}{15} : (- \frac{2}{10})[/tex]
= [tex] \frac{11}{15} * (-\frac{10}{2})[/tex]
= [tex]-\frac{11}{3} [/tex] <== SIMPLIFIER
