Question

aflati cat la suta reprezinta 20 din numarul; 40 50 80 100 200 250 400 10



dau coroana

Answer 1

$\frac{x}{100} \times 40 = 20$

$\frac{x}{10} \times 4 = 20$

$\frac{x}{5} \times 2 = 20$

$\frac{2x}{5} = 20$

$2x = 5 \times 20$

$2x = 100$

$x = \frac{100}{2}$

$x = 50 \: \%$

$\frac{x}{100} \times 50 = 20$

$\frac{x}{10} \times 5 = 20$

$\frac{x}{2} = 20$

$x = 2 \times 20$

$x = 40 \: \%$

$\frac{x}{100} \times 80 = 20$

$\frac{x}{10} \times 8 = 20$

$\frac{x}{5} \times 4 = 20$

$\frac{4x}{5} = 20$

$4x = 5 \times 20$

$4x = 100$

$x = \frac{100}{4}$

$x = 25 \: \%$

$\frac{x}{100} \times 100 = 20$

$x = 20 \: \%$

$\frac{x}{100} \times 200 = 20$

$2x = 20$

$x = \frac{20}{2}$

$x = 10 \: \%$

$\frac{x}{100} \times 250 = 20$

$\frac{x}{10} \times 25 = 20$

$\frac{x}{2} \times 5 = 20$

$\frac{5x}{2} = 20$

$5x = 2 \times 20$

$5x = 40$

$x = \frac{40}{5}$

$x = 8 \: \%$

$\frac{x}{100} \times 400 = 20$

$4x = 20$

$x = \frac{20}{4}$

$x = 5 \: \%$

$\frac{x}{100} \times 10 = 20$

$\frac{x}{10} = 20$

$x = 10 \times 20$

$x = 200 \: \%$