38. Найдите сумму или разность: 11/12 + 9/16; 1/4 − 1/5; 7/9 − 1/2; 2/3 + 1/5; 2/3 + 5/9; 45/49 + 3/7; 1/4 + 1/5; 5/6 − 7/36; 2/3 + 5/9; 1/2 + 1/8.

1. \(\frac{11}{12}+\frac{9}{16}=\frac{44}{48}+\frac{27}{48}=\frac{71}{48}=1\frac{23}{48}\).
2. \(\frac14-\frac15=\frac5{20}-\frac4{20}=\frac1{20}\).
3. \(\frac79-\frac12=\frac{14}{18}-\frac9{18}=\frac5{18}\).
4. \(\frac23+\frac15=\frac{10}{15}+\frac3{15}=\frac{13}{15}\).
5. \(\frac23+\frac59=\frac69+\frac59=\frac{11}{9}=1\frac29\).
6. \(\frac{45}{49}+\frac37=\frac{45}{49}+\frac{21}{49}=\frac{66}{49}=1\frac{17}{49}\).
7. \(\frac14+\frac15=\frac5{20}+\frac4{20}=\frac9{20}\).
8. \(\frac56-\frac7{36}=\frac{30}{36}-\frac7{36}=\frac{23}{36}\).
9. \(\frac23+\frac59=\frac69+\frac59=\frac{11}{9}=1\frac29\).
10. \(\frac12+\frac18=\frac48+\frac18=\frac58\).

Ответ: \(1\frac{23}{48};\ \frac1{20};\ \frac5{18};\ \frac{13}{15};\ 1\frac29;\ 1\frac{17}{49};\ \frac9{20};\ \frac{23}{36};\ 1\frac29;\ \frac58\).