[tex]a)\\\frac38+\frac23=\frac{9}{24}+\frac{16}{24}=\frac{25}{24}=1\frac1{24}\\b)\\1\frac14+3\frac56=\frac54+\frac{23}6=\frac{15}{12}+\frac{46}{12}=\frac{61}{12}=5\frac1{12}\\c)\\\frac79-\frac34=\frac{28}{36}-\frac{27}{36}=\frac1{36}\\d)\\2\frac34-1\frac58=\frac{11}4-\frac{13}8=\frac{22}8-\frac{13}8=\frac98=1\frac18[/tex]
