Page 8 - Mathematics Literacy Grade 11
P. 8

Unit 3: Inverse relationship

               The third type of relationship is where there is an inverse relationship between two
               variables such that when one increases, the other decreases, but the product of the
               values always remains the same.

               Example:  an increase in the number of builders decreases the number of hours it
               will  take  to  build a  house. When  sharing  an  amount  of  money  equally,  the  more
               people the fewer amounts each will get.

               The graph bellow is an example of an inverse relationship. Medication  is used in
               the treatment of HIV in order to slow down the progression of the disease. These
               medications are referred to as "anti-retroviral" (ARVs). When taken correctly ARVs
               can reduce the viral load in the blood. The viral load measures the amount of virus
               in the blood. The graph shows us that the longer someone is on ARVs the lower
               the viral load of that person.
























                Exercise 1

                1.  Mickey  pays  R599  per  month  to  watch  DSTV  channels.  The  table  below
                    shows how many hours Mickey watched television for five months and how
                    much he had to pay every month:











               1.1   Write down the dependent and independent variables.

               1.2  Describe how the two variables change in each row. Do they display any
                     patterns?








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