1. Răspuns:
x=1
Explicație pas cu pas:
[tex]\frac{8}{x+11}=\frac{2}{3}\\ 2(x+11)=3*8\\2x+22=24\\2x=24-22\\2x=2\\x=1[/tex]
2. Raspuns:
[tex]\frac{25}{4}[/tex]
Explicatie pas cu pas:
[tex]\frac{b}{a}=\frac{5}{4} => \left \{ {{b=5} \atop {a=4}} \right. \\\frac{5a+b}{a}=\frac{5*4+5}{4}\\\\\frac{20+5}{4}=\frac{25}{4}[/tex]
3. Raspuns:
[tex]m=31,2g[/tex]
Explicatie pas cu pas:
[tex]6 cm^{3} =46,8g\\1 cm^{3}=\frac{46,8g}{6} \\1cm^{3}=7,8g\\4cm^{3}=4*1cm^{3}\\4cm^{3}=4*7,8 g\\4cm^{3}=31,2g => m=31,2g[/tex]
