326. Найдите значение выражения: а) 1/2 + 5/8; б) 3/4 − 1/2; в) 7/10 − 3/5; г) 5/7 − 2/14; д) 5/9 − 5/12; е) 7/12 − 7/20; ж) 5/6 + 3/8; з) 19/21 − 11/15; и) 21/22 − 3/55; к) 5/42 + 10/63; л) 11/21 − 2/35; м) 5/24 + 7/60.

1. \(\frac12+\frac58=\frac48+\frac58=\frac98=1\frac18\).
2. \(\frac34-\frac12=\frac34-\frac24=\frac14\).
3. \(\frac7{10}-\frac35=\frac7{10}-\frac6{10}=\frac1{10}\).
4. \(\frac57-\frac2{14}=\frac57-\frac17=\frac47\).
5. \(\frac59-\frac5{12}=\frac{20}{36}-\frac{15}{36}=\frac5{36}\).
6. \(\frac7{12}-\frac7{20}=\frac{35}{60}-\frac{21}{60}=\frac{14}{60}=\frac7{30}\).
7. \(\frac56+\frac38=\frac{20}{24}+\frac9{24}=\frac{29}{24}=1\frac5{24}\).
8. \(\frac{19}{21}-\frac{11}{15}=\frac{95}{105}-\frac{77}{105}=\frac{18}{105}=\frac6{35}\).
9. \(\frac{21}{22}-\frac3{55}=\frac{105}{110}-\frac6{110}=\frac{99}{110}=\frac9{10}\).
10. \(\frac5{42}+\frac{10}{63}=\frac{15}{126}+\frac{20}{126}=\frac{35}{126}=\frac5{18}\).
11. \(\frac{11}{21}-\frac2{35}=\frac{55}{105}-\frac6{105}=\frac{49}{105}=\frac7{15}\).
12. \(\frac5{24}+\frac7{60}=\frac{25}{120}+\frac{14}{120}=\frac{39}{120}=\frac{13}{40}\).

Ответ: а) \(1\frac18\); б) \(\frac14\); в) \(\frac1{10}\); г) \(\frac47\); д) \(\frac5{36}\); е) \(\frac7{30}\); ж) \(1\frac5{24}\); з) \(\frac6{35}\); и) \(\frac9{10}\); к) \(\frac5{18}\); л) \(\frac7{15}\); м) \(\frac{13}{40}\).