India’s No.1 Educational Platform For UPSC,PSC And All Competitive Exam

Download Our App

A shopkeeper cheats to the extent of 10% while buying as well as selling, by using false weights. His total gain is -

110%
211%
320%
421%

Answer:- 4

Explanation:-

Solution:

\begin{aligned} Rule : Gain % \\ = \frac{{(100 + common gain %)}^{2}}{100} - 100 \\ ∴ Gain % \\ = [\frac{{(100 + 10)}^{2}}{100} - 100] % \\ = (\frac{12100 - 10000}{100}) % \\ = 21 % \end{aligned}

$\eqalign{ & {\text{Rule}}:{\text{Gain}}\% \cr & = \frac{{{{\left( {100 + {\text{common gain}}\% } \right)}^2}}}{{100}} - 100 \cr & \therefore {\text{Gain }}\% \cr & = \left[ {\frac{{{{\left( {100 + 10} \right)}^2}}}{{100}} - 100} \right]\% \cr & = \left( {\frac{{12100 - 10000}}{{100}}} \right)\% \cr & = 21\% \cr}$

Workspace Report

Post your Comments

", "dateCreated": "7/24/2019 10:09:12 AM", "author": { "@type": "Person", "name": "Nitin Sir" } }, "suggestedAnswer": { "@type": "Answer", "text": "

Solution:

\begin{aligned} Rule : Gain % \\ = \frac{{(100 + common gain %)}^{2}}{100} - 100 \\ ∴ Gain % \\ = [\frac{{(100 + 10)}^{2}}{100} - 100] % \\ = (\frac{12100 - 10000}{100}) % \\ = 21 % \end{aligned}

$\eqalign{ & {\text{Rule}}:{\text{Gain}}\% \cr & = \frac{{{{\left( {100 + {\text{common gain}}\% } \right)}^2}}}{{100}} - 100 \cr & \therefore {\text{Gain }}\% \cr & = \left[ {\frac{{{{\left( {100 + 10} \right)}^2}}}{{100}} - 100} \right]\% \cr & = \left( {\frac{{12100 - 10000}}{{100}}} \right)\% \cr & = 21\% \cr}$ ", "dateCreated": "7/24/2019 10:09:12 AM" } }

Test

Classes

E-Book