Question

A person buys electronic goods worth Rs.10000 for which the sales tax is 4% and other material worth Rs.15000 for which sales tax is 6%. He manufactures a gadget using all these and sells it at a 15% profit. What is his selling price?

Answer 1

Hint: We are given with the total cost price of the materials or goods and percentage profit that a person earned. Since we are given the percentage profit we can calculate the selling price using the formula for percentage profit.

Complete step by step answer:

We are given that, he buys electronic goods worth Rs.10000.
But for this sales tax is 4%.
So along with the goods cost price he needs to pay tax amount. That is 4% of that goods amount in addition.
 \[
   = 10000 + \dfrac{4}{{100}} \times 10000 \\
   \Rightarrow 10000 + 400 \\
   \Rightarrow 10400 \\
 \]
Now he purchased other material worth Rs.15000.
But for this sales tax is 6%.
So total amount he paid will be cost price of material along with the 6% tax of that amount.
\[
   = 15000 + \dfrac{6}{{100}} \times 15000 \\
   \Rightarrow 15000 + 900 \\
   \Rightarrow 15900 \\
 \]
Now his total cost price
\[
   = 10400 + 15900 \\
   \Rightarrow 26300 \\
 \]
Further he sells it at 15% profit. So to find the selling price we will use the formula given below,
\[
  \% profit = \dfrac{{profit}}{{C.P.}} \times 100 \\
   \Rightarrow 15\% profit = \dfrac{{S.P. - C.P.}}{{C.P.}} \times 100 \\
   \Rightarrow 15 = \dfrac{{S.P. - 26300}}{{26300}} \times 100 \\
   \Rightarrow 15 \times 263 = S.P. - 26300 \\
   \Rightarrow 3945 = S.P. - 26300 \\
   \Rightarrow S.P. = 30245 \\
 \]
Now,
Thus selling price of his gadget is Rs.30245

Note: A student should be familiar with the concept and formulas of profit and loss. Here the person has paid tax on both the purchased good and materials. So students generally forget to add the tax also in C.P.
Additional information: The price at which the product is bought is called cost price. It is denoted by C.P. The price at which the product I sold is called selling price. It is denoted by S.P. If S.P. > C.P., it is a profitable transaction. Profit is given by S.P.-C.P. If S.P < C.P., it is a loss transaction. Loss is given by C.P.-S.P.