Question

A dishonest shopkeeper sells his goods on cost price, but weighs less and gains 25%. How much he weighs for a kilogram.

Answer 1

let x
$sp \: = 100 \\ profit \: = 25\% \\ cp = \frac{100 \times 100}{125} \\ cp \: = 80 \\ if \: 100 \: costs \: for \: 1kg \\ then \: 1 \: costs \: for \frac{1}{100} kg \\ therefore \: 80 \: cost \: for \: \frac{1}{100} \times 80 kg= \frac{4}{5} kg = 800gm. \\ thereforet \\ \: the \: shopkeeper \: weighs \: 800gm.$