Question

а) 512x+415x=0,51                   б)x-0,2=815

            решите плиз

Answer 1

а) 512x+415x=0,51

25/60х+16/60х=51/100

41/60х=51/100

х=51/100:41/60

х=51/100*60/41

х=51*60/100*41

х=3060/4100

х=153/205

б)x-0,2=815

х=8/15+2/10

х=16/30+6/30

х=22/30

х=11/15

Answer 2

а) $frac{5}{12}x+frac{4}{15}x=0,51$

 

$frac{25x+16x}{60}=frac{51}{100}$

 

$frac{41x}{60}=frac{51}{100}$

 

$41x=frac{51cdot60}{100}$

 

$41x=frac{306}{10}$

 

$x=frac{306}{10}:41=frac{306}{10}cdotfrac{1}{41}=frac{306}{410}=frac{153}{205}$

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б) $x-0,2=frac{8}{15}$

 

$x-frac{1}{5}=frac{8}{15}$

 

$x=frac{8}{15}+frac{1}{5}=frac{8+3}{15}=frac{11}{15}$