Percentage I

Q1:  

The price of a watch is increased by 30% and then decreased by 30%.Then how much percentage will the price for watch be change?

Ans:Formula=A x A/100

          Here A=30

          Price Change in Percentage = 30 x 30/100

         =900/100

         =9% loss

Q2:  

The price of a book is decreased by 40% and then increased by 40%.Then how much percentage will the price for book be change?

Ans:Formula=A x A/100

       Here A=40

       Price Change in Percentage = 40 x 40/100

      =1600/100

      =16%  loss

Q3:  

The price of a cycle is decreased by 60% and then increased by 60%.Then how much percentage will the price for cycle be change?

Ans:Formula=A x A/100

Here A=60

            Price Change in Percentage = 60x 60/100

                                                                    =3600/100

                                                                    =36%  loss

Q4:  

The price of a book is 800,which in turn decreased by 20% and then increased by 20%.What will be the new price of the book?

Ans: Formula= A x A/100

            Here A=20

            Price Change in Percentage = 20x 20/100

                                                                    =400/100

                                                                    =4%  loss

          New price of the watch           =800-(4 x 800/100)

                                                                    =768

Q5:  

The price of a TV is decreased by 25%.As a result of which the sales increased by 20%.What will be the effect on the total revenue of the shop?

Ans: Assume,                            Price            Sales            Income

            Before Price Change              100              100             100 x 100 =10000

            When price decreased            75               120             75 x 120       = 9000  

            total revenue change= (10000-9000) x 100/10000 =1000 x 100/10000 = 10%    decreased
Q6:  

The price of a cycle is decreased by 10%.As a result of which the sales increased by 20%.What will be the effect on the total revenue of the shop?

Ans:  Assume,                           Price             Sales           Income

            Before Price Change              100              100             100 x 100 =10000

            When price decreased            90               120             90 x 120       = 10800

           total revenue change= (10000-10800) x 100/10000 =800 x 100/10000 = 8%    increased

Q7:  

The price of a TV is increased by 20%.As a result of which the sales decreased by 20%.What will be the effect on the total revenue of the shop?

Ans: Assume,                              Price            Sales          Income

            Before Price Change               100               100           100 x 100 =10000

            When price decreased            120               80             90 x 120       = 9600

           total revenue change= (10000-9600) x 100/10000 =400 x 100/10000 = 4%    decreased