The Cost Price of item B is \(Rs. 200/-\) more than the cost price of item \(A\). Item \(A \)was sold at a profit of \(20\) % and item \(B \) was sold at a loss of \(30\) %. If the respective ratio of Selling Prices of items \(A \) and \(B\) is \(6 : 7,\) what is the cost price of item \(B\) ?
Answer: D
Let the Cost Price of item \(A\) be \(x\)
Cost Price of item \(B \) is \(x + 200.\)
\(\frac{(\frac{120}{100} \times x)}{(x + 200) \times \frac{70}{100}} = \frac{6}{7} \)
\(\frac{120x}{(x + 200) \times 70} = \frac{6}{7}\)
\(\frac{20x}{10(x + 200)} = 1\)
\(x = Rs 200.\)
Cost Price of item \(B\) is \(200 + 200 = Rs 400.\)