Răspuns :
[tex]a) \frac{x}{100} \times 65 = 13[/tex]
[tex] \frac{65x}{100} = 13[/tex]
[tex]65x = 1300[/tex]
[tex]x = \frac{1300}{65} [/tex]
[tex]x = 20[/tex]
[tex]b) \frac{x}{100} \times 96 = 24[/tex]
[tex] \frac{96x}{100} = 24[/tex]
[tex]96x = 2400[/tex]
[tex]x = \frac{2400}{96} [/tex]
[tex]x = 25[/tex]
[tex]c) \frac{x}{100} \times 72 = 9[/tex]
[tex] \frac{72x}{100} = 9[/tex]
[tex]72x = 900[/tex]
[tex]x = \frac{900}{72} [/tex]
[tex]x = 12.5[/tex]
[tex]d) \frac{x}{100} \times 300 = 12[/tex]
[tex] \frac{300x}{100} = 12[/tex]
[tex]3x = 12[/tex]
[tex]x = \frac{12}{3} [/tex]
[tex]x = 4[/tex]
[tex]e) \frac{x}{100} \times 800 = 52[/tex]
[tex] \frac{800x}{100} = 52[/tex]
[tex]8x = 52[/tex]
[tex]x = \frac{52}{8} [/tex]
[tex]x = 6.5[/tex]
[tex] \frac{65x}{100} = 13[/tex]
[tex]65x = 1300[/tex]
[tex]x = \frac{1300}{65} [/tex]
[tex]x = 20[/tex]
[tex]b) \frac{x}{100} \times 96 = 24[/tex]
[tex] \frac{96x}{100} = 24[/tex]
[tex]96x = 2400[/tex]
[tex]x = \frac{2400}{96} [/tex]
[tex]x = 25[/tex]
[tex]c) \frac{x}{100} \times 72 = 9[/tex]
[tex] \frac{72x}{100} = 9[/tex]
[tex]72x = 900[/tex]
[tex]x = \frac{900}{72} [/tex]
[tex]x = 12.5[/tex]
[tex]d) \frac{x}{100} \times 300 = 12[/tex]
[tex] \frac{300x}{100} = 12[/tex]
[tex]3x = 12[/tex]
[tex]x = \frac{12}{3} [/tex]
[tex]x = 4[/tex]
[tex]e) \frac{x}{100} \times 800 = 52[/tex]
[tex] \frac{800x}{100} = 52[/tex]
[tex]8x = 52[/tex]
[tex]x = \frac{52}{8} [/tex]
[tex]x = 6.5[/tex]