1. Найдите сумму или разность: 1) a)+; 3 2) a) - 1 13 : 3) a); 34 51 6)- 7 6)20+ 1 1. 14 2. 3' 7 6) 30-50 90 2. Найдите значение выражения: 1) a) 7+5,31+9+13,49; 2) a) 8,31-(4,29+3,721); в) 2+5; B) 3-1; 3 B) 6-10 14 б) 62,7+8,31+5,79+0,07; б) (8,21+9,73)-0,001.

Выполним вычисления:

1. 1) a)

   $$ \frac{1}{3} + \frac{5}{6} = \frac{2}{6} + \frac{5}{6} = \frac{7}{6} = 1\frac{1}{6} $$

2. 1) б)

   $$ \frac{5}{7} - \frac{1}{14} = \frac{10}{14} - \frac{1}{14} = \frac{9}{14} $$

3. 1) в)

   $$ 2\frac{2}{3} + 5\frac{5}{12} = 2\frac{8}{12} + 5\frac{5}{12} = 7\frac{13}{12} = 8\frac{1}{12} $$

4. 2) a)

   $$ \frac{3}{11} - \frac{1}{13} = \frac{39}{143} - \frac{11}{143} = \frac{28}{143} $$

5. 2) б)

   $$ \frac{7}{20} + \frac{2}{3} = \frac{21}{60} + \frac{40}{60} = \frac{61}{60} = 1\frac{1}{60} $$

6. 2) в)

   $$ 3\frac{2}{15} - 1\frac{1}{7} = 3\frac{14}{105} - 1\frac{15}{105} = 2\frac{119}{105} - 1\frac{15}{105} = 1\frac{104}{105} $$

7. 3) a)

   $$ \frac{5}{34} - \frac{41}{51} = \frac{5 \cdot 3}{34 \cdot 3} - \frac{41 \cdot 2}{51 \cdot 2} = \frac{15}{102} - \frac{82}{102} = -\frac{67}{102} $$

8. 3) б)

   $$ 3\frac{1}{30} - 5\frac{7}{90} = 3\frac{3}{90} - 5\frac{7}{90} = 3\frac{3}{90} - 5\frac{7}{90} = -2\frac{4}{90} = -2\frac{2}{45} $$

9. 3) в)

   $$ 6\frac{1}{7} - 10\frac{3}{14} = 6\frac{2}{14} - 10\frac{3}{14} = -4\frac{1}{14} $$

1. 1) a)

   $$ 7 + 5{,}31 + 9 + 13{,}49 = 12{,}31 + 22{,}49 = 34{,}8 $$

2. 1) б)

   $$ 62{,}7 + 8{,}31 + 5{,}79 + 0{,}07 = 71{,}01 + 5{,}86 = 76{,}87 $$

3. 2) a)

   $$ 8{,}31 - (4{,}29 + 3{,}721) = 8{,}31 - 8{,}011 = 0{,}299 $$

4. 2) б)

   $$ (8{,}21 + 9{,}73) - 0{,}001 = 17{,}94 - 0{,}001 = 17{,}939 $$