Question

selling price is 20000 profit is 30% cp?​

Answer 1

$sp = rs.20000 \\ p\% = 30\% \\ let \: cp \: be \: x \\ then \: p = sp - x = 20000 - x \\ p\% = \frac{p}{cp} \times 100 \\ 30 = \frac{20000 - x}{x} \times 100 \\ \frac{30}{100} = \frac{20000 - x}{x} \\ \frac{3x}{10} = 20000 - x \\ 3x = 200000 - 10x \\ 3x + 10x = 200000 \\ 13x = 200000 \\ x = \frac{200000}{13} \\ x = rs.15384.67$