Răspuns :
[tex]a) \frac{50}{100} \times x = 37[/tex]
[tex] \frac{1}{2} \times x = 37[/tex]
[tex] \frac{x}{2} = 37[/tex]
[tex]x = 2 \times 37[/tex]
[tex]x = 74[/tex]
[tex]b) \frac{10}{100} \times x = 87[/tex]
[tex] \frac{1}{10} \times x = 87[/tex]
[tex] \frac{x}{10} = 87[/tex]
[tex]x = 10 \times 87[/tex]
[tex]x = 870[/tex]
[tex]c) \frac{70}{100} \times x = 98[/tex]
[tex] \frac{7x}{10} = 98[/tex]
[tex]7x = 10 \times 98[/tex]
[tex]7x = 980 \: | \div 7[/tex]
[tex]x = 140[/tex]
[tex]d) \frac{12}{100} \times x = 51[/tex]
[tex] \frac{3x}{25} = 51[/tex]
[tex]3x = 25 \times 51[/tex]
[tex]3x = 1275 \: | \div 3[/tex]
[tex]x = 425[/tex]
[tex]e) \frac{75}{100} \times x = 57[/tex]
[tex] \frac{3x}{4} = 57[/tex]
[tex]3x = 4 \times 57[/tex]
[tex]3x = 228 \: | \div 3[/tex]
[tex]x = 76[/tex]
[tex]f) \frac{24}{100} \times x = 42[/tex]
[tex] \frac{6x}{25} = 42[/tex]
[tex]6x = 25 \times 42[/tex]
[tex]6x = 1050 \: | \div 6[/tex]
[tex]x = 175[/tex]
[tex] \frac{1}{2} \times x = 37[/tex]
[tex] \frac{x}{2} = 37[/tex]
[tex]x = 2 \times 37[/tex]
[tex]x = 74[/tex]
[tex]b) \frac{10}{100} \times x = 87[/tex]
[tex] \frac{1}{10} \times x = 87[/tex]
[tex] \frac{x}{10} = 87[/tex]
[tex]x = 10 \times 87[/tex]
[tex]x = 870[/tex]
[tex]c) \frac{70}{100} \times x = 98[/tex]
[tex] \frac{7x}{10} = 98[/tex]
[tex]7x = 10 \times 98[/tex]
[tex]7x = 980 \: | \div 7[/tex]
[tex]x = 140[/tex]
[tex]d) \frac{12}{100} \times x = 51[/tex]
[tex] \frac{3x}{25} = 51[/tex]
[tex]3x = 25 \times 51[/tex]
[tex]3x = 1275 \: | \div 3[/tex]
[tex]x = 425[/tex]
[tex]e) \frac{75}{100} \times x = 57[/tex]
[tex] \frac{3x}{4} = 57[/tex]
[tex]3x = 4 \times 57[/tex]
[tex]3x = 228 \: | \div 3[/tex]
[tex]x = 76[/tex]
[tex]f) \frac{24}{100} \times x = 42[/tex]
[tex] \frac{6x}{25} = 42[/tex]
[tex]6x = 25 \times 42[/tex]
[tex]6x = 1050 \: | \div 6[/tex]
[tex]x = 175[/tex]