Q1. Following are the car parking charges near a railway station upto
                               4 hours                Rs. 60
                               8 hours                Rs.100
                               12 hours              Rs. 140
                               24 hours              Rs.180
Check if the parking charges are in direct proportion to the parking time.



Answers (1)

We say that x and y are in direct proportion, if  \frac{x}{y}=k or  x = ky.

Hence in the given problem we have,

Charges for the parking :                      

y x
4 hours Rs. 60
8 hours Rs. 100
12 hours Rs. 140
24 hours Rs. 180

considering x to be charged to be paid and to be the parking time.

Then we calculate  \frac{x}{y},

For:-    4 hours:  \frac{60}{4}=\frac{15}{1}                     8 hours : \frac{100}{8}=\frac{25}{2}

         12 hours : \frac{140}{12}=\frac{35}{3}                 24 hours:  \frac{180}{24}=\frac{15}{2}            

Clearly \frac{x}{y} is not equal to some constant 'k',  then we can say that 

Parking charges are not in direct proportion to parking time.