a: =6x2/5-3/10
=12/5-3/10
=24/10-3/10=21/10
b: =1/2+4/3=3/6+8/6=11/6
c: =5/6+1/4=10/12+3/12=13/12
a) \(6\div\dfrac{5}{2}-\dfrac{3}{10}=\dfrac{6}{1}\div\dfrac{5}{2}-\dfrac{3}{10}=\dfrac{12}{5}-\dfrac{3}{10}=\dfrac{24}{10}-\dfrac{3}{10}=\dfrac{21}{10}\)
b) \(\dfrac{4}{6}\div\dfrac{4}{3}+\dfrac{4}{3}=\dfrac{1}{2}+\dfrac{4}{3}=\dfrac{3}{6}+\dfrac{8}{6}=\dfrac{11}{6}\)
c) \(\dfrac{5}{2}\times\dfrac{1}{3}+\dfrac{1}{4}=\dfrac{5}{6}+\dfrac{1}{4}=\dfrac{10}{12}+\dfrac{3}{12}=\dfrac{13}{12}\)
d) \(\dfrac{6}{7}\div\left(\dfrac{1}{2}\times\dfrac{3}{4}\right)-\dfrac{5}{8}=\dfrac{6}{7}\div\dfrac{3}{8}-\dfrac{5}{8}=\dfrac{16}{7}-\dfrac{5}{8}=\dfrac{93}{56}\)