An item costing Rs. 840 was sold by a shopkeeper at a gain of 10% and it was again sold by the new buyer at a loss of 5%. Find selling price of the item is = ?

Answer: Option A

According to the question,
Cost price = Rs. 840
10% Profit on cost price
$$\begin{array}{rl}& =\frac{10}{100}\times 840\\ & =\text{Rs}\text{. }84\\ & \therefore \text{Selling price}\\ & =840+84\\ & =\text{Rs}\text{. 924}\end{array}$$
New buyer cost price
$$=\text{Rs}\text{. 924}$$
5% loss on Cost price
$$\begin{array}{rl}& =\frac{5}{100}\times 924\\ & =\text{Rs}\text{. }46.2\\ & \text{Selling price}\\ & =\text{Rs}\text{. 924}-46.2\\ & =\text{Rs}\text{. }877.80\end{array}$$