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                 \ 06-Jan-2025  Bharat Arora   Proof-7             Reader’s Sign _______________________ Date __________





                Profit/Loss Per cent

                The percentage of profit or loss is always calculated on the cost price.


                                     Profit (gain) % =   Profit  × 100%  And Loss % =   Loss  × 100%
                                                         CP                            CP
                Example 6: Lalan bought a second-hand motorcycle for
                `20,500, then spent `4,500 on its repairs and sold it for                  Think and Answer
                `30,000. Find his loss or gain per cent.
                                                                                       Madhu: For the school fair (mela),
                Solution: Cost Price (CP) = `20,500 + `4,500 = `25,000                 I am going to put up a stall of lucky
                                        (overhead expenses are added to CP)            dips. I will charge `20 for one lucky
                                                                                       dip, but I will put items that are
                                  Selling Price (SP) = `30,000                         worth `10.

                Since,                            SP > CP                              Vijay: So you are making a profit
                                                                                          10
                Therefore, he made a profit = `30,000 – `25,000 = `5,000               of  20   × 100% = 50%.

                                                        Profit                         Madhu: No, I will spend `5 on paper
                So,                         Profit % =        × 100%                   to wrap the gift and tape. So, my
                                                         CP                            expenditure is `15. This way, I will
                                                        5000
                                                     =        × 100% = 20%                   5             1
                                                        25000                          gain   15  × 100% = 33 % only.
                                                                                                           3
                Example 7: If the CP of 10 bananas is equal to the SP of 12
                bananas, find the profit or loss per cent in this deal.

                Solution:  Let the CP of 1 banana = `1
                So,               CP of 12 bananas = `12

                Since,            SP of 12 bananas = CP of 10 bananas = `10

                Since, SP < CP, so it is a loss.                                        1.  What do you think about the
                                                                                          calculation done by Vijay?
                                                Loss = CP – SP = `12 – `10 = `2
                                                                                        2.  Recognise overhead expenses.
                                                        Loss                              What is Madhu’s actual profit:
                                             Loss % =        × 100%
                                                                                                    1
                                                        CP                                25% or 33 %?
                                                        2               2                           3
                                                     =      × 100% = 16 %
                                                        12              3

                Finding SP/CP when Profit/Loss Per cent is Given

                When profit % or loss % is given, then to calculate the selling price (SP) or the cost price (CP), we
                use the following formulae:

                If the profit % (P%) is given, then
                                                                                          100
                                                  SP =      100 + P%      × CP and   CP =     100 + P%      × SP
                                                            100

                If the loss % (L%) is given, then
                                                                                          100
                                                  SP =      100 − L%      × CP and   CP =     100 − L%      × SP
                                                           100

                                                                  171                                 Comparing Quantities
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