In a research conducted by Road Transport and Safety Agency (RTSA) three cars Toyota, Mazda and Nissan were considered.

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In a research conducted by Road Transport and Safety Agency
(RTSA) three cars Toyota, Mazda and Nissan were considered. In
finding out the index number some fixed fuel consumptions were
assigned to the three models in each type of the car. The table
below provides the information regarding the fuel consumption of
three cars according to the three models and also the total fuel
consumption by each car.
Type of Car
Model
Total Fuel Consumption
A
B
C
Toyota
1
2
3
11
Mazda
2
4
5
21
Nissan
3
5
6
27