Question

Решить уравнения
( х+2 3\13)- 1 7\26= 4 5 \39

8 7\18- (1 11\15+у)= 3 4\15+2 13\45
найди значение выражения наиболее удобным способом
2 9/49 + (7 3/85 + 3 40/49)

(5 16/39 + 1 6/11) - 2 16/39

7 13/14 - ( 2 13/14 + 4 17/25)

Answer 1

$1.\;\;(x+2\frac3{13})- 1\frac7{26}= 4\frac5{39}\\x+\frac{29}{13}-\frac{33}{26}=\frac{151}{39}\\ x+\frac{58-33}{26}=\frac{151}{39}\\x=\frac{151}{39}-\frac{25}{26}\\x=\frac{322-75}{78}\\x=\frac{247}{78}=\farc{19}6=3\frac16\\ 2.\;\;8\frac7{18}- \left(1\frac{11}{15}+y\right)= 3\frac4{15}+2\frac{13}{45}\\ \frac{151}{18}- \frac{26}{15}+y\right)=\frac{49}{15}+\frac{103}{45}\\\frac{755-156}{90}+y=\frac{147+103}{45}\\y=\frac{250}{45}-\frac{599}{90}\\y=\frac{500-599}{90}\\y=-\frac{99}{90}=-1\frac9{90}=-1\frac1{10}$
$3.\;\;2\frac9{49} + \left(7\frac3{85} + 3\frac{40}{49}\right)=\frac{107}{49} + \frac{598}{85} + \frac{187}{49}=\frac{294}{49}+\frac{598}{85}=6+\frac{598}{85}=\\=\frac{510+598}{85}=\frac{1108}{85}=13\frac3{85}\\ 4.\;\;\left(5\frac{16}{39} + 1\frac6{11}\right) - 2\frac{16}{39}=\frac{211}{39}+\frac{17}{11}-\frac{94}{29}=\frac{117}{39}+\frac{17}{11}=3+\frac{17}{11}=\frac{50}{11}=4\frac6{11}$
$5.\;\;7\frac{13}{14} - \left( 2\frac{13}{14} + 4\frac{17}{25}\right)=\frac{111}{14}-\frac{41}{14}+\frac{117}{25}=\frac{70}{14}+\frac{117}{25}=5+\frac{117}{25}=\\ \frac{125+117}{25}=\frac{242}{25}=9\frac{17}{25}$