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a) \(\dfrac{6}{13}:\left(\dfrac{1}{2}-x\right)=\dfrac{15}{39}\)
\(\dfrac{1}{2}-x=\dfrac{6}{13}:\dfrac{15}{39}\)
\(\dfrac{1}{2}-x=\dfrac{6}{5}\)
\(x=\dfrac{1}{2}-\dfrac{6}{5}\)
\(x=-\dfrac{7}{10}\)
b) \(3\times\left(\dfrac{x}{4}+\dfrac{x}{28}+\dfrac{x}{70}+\dfrac{x}{130}\right)=\dfrac{60}{13}\)
\(3\times x\times\left(\dfrac{1}{4}+\dfrac{1}{28}+\dfrac{1}{70}+\dfrac{1}{130}\right)=\dfrac{60}{13}\)
\(x\times\left(\dfrac{3}{1\times4}+\dfrac{3}{4\times7}+\dfrac{3}{7\times10}+\dfrac{3}{7\times13}\right)=\dfrac{60}{13}\)
\(x\times\left(1-\dfrac{1}{4}+\dfrac{1}{4}-\dfrac{1}{7}+\dfrac{1}{7}-\dfrac{1}{10}+\dfrac{1}{10}-\dfrac{1}{13}\right)=\dfrac{60}{13}\)
\(x\times\left(1-\dfrac{1}{13}\right)=\dfrac{60}{13}\)
\(x\times\dfrac{12}{13}=\dfrac{60}{13}\)
\(x=\dfrac{60}{13}:\dfrac{12}{13}\)
\(x=5\)
a. ( x - 1/2 ) x 5/3= 7/4 - 1/2
(x -1/2 ) x 5/3 = 5/4
x - 1/2 = 5/4 : 5/3
x - 1/2 = 3/4
x = 3/4 + 1/2
x = 5/4
b . 6/13 : ( 1/2 + x ) = 15/39
1/2 + x = 6/13- 15/39
1/2 + x = 1/13
x = 1/13 - 1/2
x = -11/26
c. 16/3 : (1/2+ x ) = 15/39
1/2 + x = 16/3 - 15/69
1/2 + x = 353/69
x = 353/69 - 1/2
x = 637/138
a) 92 : 0,01 = 9200 92 x 100 = 9200 64 : 0,01= 6400
b) 25 : 0,5 = 50 25 x 2 = 50 39 : 0,5 = 78
c) 32 : 0,25 = 128 32 x 4 = 128 15 : 0,25 = 60
y x 6 + y x 3 + y = 80
y x 6 + y x 3 + y x 1 = 80
y x (6+3+1)=80
y x 10 =80
y =80:10
y =8
a) \(y\times6+y\times3+y=80\)
\(\Leftrightarrow y\times\left(6+3+1\right)=80\)
\(\Leftrightarrow y\times10=80\)
\(\Leftrightarrow y=80\div10\)
\(\Leftrightarrow y=8\)
b) \(y+y\div0,5+y\div0,25+y\div0,125=15\)
\(\Leftrightarrow y+y\times2+y\times4+y\times8=15\)
\(\Leftrightarrow y\times\left(1+2+4+8\right)=15\)
\(\Leftrightarrow y\times15=15\)
\(\Leftrightarrow y=1\)
\(\frac{1}{2}+x=\frac{6}{13}:\frac{15}{39}=\frac{6}{5}\)
=>\(x=\frac{6}{5}-\frac{1}{2}=\frac{7}{10}\)
6/13 : (1/2 + x) = 15/39 1/2 + x = 6/13 : 15/39 1/2 + x = 6/5 x = 6/5 - 1/2 x = 7/10
a)
0,9 x 438 x 2 + 0,18 x 2520 + 0,6 x 310 x 3
= 0,9 x 2 x 438 + 0,18 x 2520 + 0,6 x 3 x 310
= 0,18 x 438 + 0,18 x 2520 + 0,18 x 310
= 0,18 x .....................
= 0,18 x ...........
= ..................
~ Hok t ~
\(\dfrac{6}{13}:\left(0,5+x\right)=\dfrac{15}{39}\)
\(\dfrac{6}{13}:\left(0,5+x\right)=\dfrac{5}{13}\)
\(0,5+x=\dfrac{6}{13}:\dfrac{5}{13}\)
\(0,5+x=\dfrac{6}{13}\cdot\dfrac{13}{5}\)
\(0,5+x=\dfrac{6}{5}\)
\(x=\dfrac{6}{5}-0,5\)
\(x=\dfrac{12}{10}-\dfrac{5}{10}\)
\(x=\dfrac{7}{10}\)
\(\dfrac{6}{13}:\left(0,5+x\right)=\dfrac{15}{39}\\ \Rightarrow\dfrac{6}{13}:\left(\dfrac{1}{2}+x\right)=\dfrac{15}{39}\\ \Rightarrow\dfrac{1}{2}+x=\dfrac{6}{13}:\dfrac{15}{39}\\ \Rightarrow\dfrac{1}{2}+x=\dfrac{6}{13}\times\dfrac{39}{15}\\ \Rightarrow\dfrac{1}{2}+x=\dfrac{6}{5}\\ \Rightarrow x=\dfrac{6}{5}-\dfrac{1}{2}=\dfrac{6\times2-5}{10}=\dfrac{7}{10}\)