1.1. Вычислите значения выражений. А: 1) 2/7 + 11/21 + 321/49; 2) (1/2 + 2/7) · 14/13; 3) (3/4 + 7/5) · 0,7 : 86/17. Б: 1) 5/6 + 7/33 + 9/22; 2) 6 1/11 : 5/8 · 9/40 + 0,01; 3) (1 − 1/11 + 1/121) : (8/20 + 4/12). В: 1) (2/47 − 3/53) · 0,2; 2) (1 − 10⁻⁴)/99 : 0,16/25; 3) 0,34 − 0,08² − 1/125 + 3/25 − 3/5 + 1.

А.

1. Приведём к знаменателю 147: \(\frac{2}{7}+\frac{11}{21}+\frac{321}{49}=\frac{42+77+963}{147}=\frac{1082}{147}\).
2. \(\left(\frac12+\frac27\right)\cdot\frac{14}{13}=\frac{11}{14}\cdot\frac{14}{13}=\frac{11}{13}\).
3. \(\left(\frac34+\frac75\right)\cdot0.7:\frac{86}{17}=\frac{43}{20}\cdot\frac7{10}\cdot\frac{17}{86}=\frac{119}{400}\).

Б.

1. \(\frac56+\frac7{33}+\frac9{22}=\frac{55+14+27}{66}=\frac{48}{33}=\frac{16}{11}\).
2. \(6\frac1{11}:\frac58\cdot\frac9{40}+0.01=\frac{67}{11}\cdot\frac85\cdot\frac9{40}+\frac1{100}=\frac{603}{275}+\frac1{100}=\frac{2413}{1100}\).
3. \(\left(1-\frac1{11}+\frac1{121}\right):\left(\frac8{20}+\frac4{12}\right)=\frac{111}{121}:\frac{11}{15}=\frac{15}{11}\).

В.

1. \(\left(\frac2{47}-\frac3{53}\right)\cdot0.2=\frac{106-141}{2491}\cdot\frac15=-\frac7{2491}\).
2. \(\frac{1-10^{-4}}{99}:\frac{0.16}{25}=\frac{9999}{10000\cdot99}\cdot\frac{25}{0.16}=\frac{101}{64}\).
3. \(0.34-0.08^2-\frac1{125}+\frac3{25}-\frac35+1=0.34-0.0064-0.008+0.12-0.6+1=0.8456\).

Ответ: А: 1) \(\frac{1082}{147}\); 2) \(\frac{11}{13}\); 3) \(\frac{119}{400}\). Б: 1) \(\frac{16}{11}\); 2) \(\frac{2413}{1100}\); 3) \(\frac{15}{11}\). В: 1) \(-\frac7{2491}\); 2) \(\frac{101}{64}\); 3) \(0.8456\).