Question

dintr-un vas plin cu apa se scade jumatate din acesta si inca 5 l ,ramanand in el 45%.Cati litti de apa incap in vas ?

Answer 1

$X-( \frac{x}{2} +5)= \frac{45}{100}$
$\frac{20x}{20} - \frac{10x}{20} - \frac{100}{20} = \frac{9x}{20}$
20X-9X-10X=100
X=100

Answer 2

100% -50% - 5l =45% 

100% -50% - 45% = 5l

5% = 5l

100%  = 100l
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[tex]\it45\% = 100\%-50\%-5 \ell \Rightarrow 45\% +5\ell =100\%-50\% \Rightarrow \\\;\\ \Rightarrow 5\ell =\it100\%-50\% -45\% \Rightarrow 5\ell = 5\% |_{\cdot 20}\Rightarrow 100\ell = 100\% .[/tex]

Deci, vasul are o capacitate de 100 litri.