[tex]a) \frac{13}5*\frac14+\frac{23}{10}=\frac{13}{20}+\frac{23}{10}=\frac{13}{20}+\frac{46}{20}=\frac{59}{20}=2\frac{19}{20}[/tex]
[tex]b) 1\frac17+\frac37*2\frac5{15}=\frac87+\frac37*\frac{35}{15}=\frac87+\frac{105}{105}=\frac87+\frac11=\frac87+\frac77=\frac{15}{7}=2\frac17[/tex]
