Given that $${{\log \,P} \over {y - z}} = {{\log \,Q} \over {z - x}} = {{\log \,R} \over {x - y}} = 10$$ for $$x \ne y \ne z$$, what is the value of the product PQR?

The price of a wire made of a superalloy material is proportional to the square of its length. The price of 10 m length of the wire is Rs. 1600. What would be the total price (in Rs.) of two wires of lengths 4 m and 6m?

A fruit seller sold a basket of fruits at 12.5% loss. Had he sold it for Rs. 108 more, he would have made a 10% gain. What is the loss in Rupees incurred by the fruit seller?

Which of the following function(s) is an accurate description of the graph for the range(s) indicated? $$\eqalign{ & (i)\,\,y = 2x + 4\,for\, - 3 \le x \le - 1 \cr & (ii)\,y = \,|x - 1|\,for\, - 1 \le x \le 2 \cr & (iii)\,y = \,\left| {\left| x \right| - 1} \right|\,for\, - 1 \le x \le 2 \cr & (iv)\,y = 1\,for\,2 \le x \le 3 \cr} $$