A dishonest dealer professes to sell his goods at cost price but uses a false weight and thus gains 15 %. For a kilogram, he uses a weight of __________ (rounded off to one digit after decimal).

869 .6 gm

+15 % = \(\frac{23}{20}\) = \(\frac{SP}{CP}\)

          CP                       SP

         20                          23

        ⇓×43.47               ⇓ ×43.47

      869.6 gm.            1000 gm. (Given)