MATHS ASSIGNMENT 2

Maths Assignment 2



Solution 1

Scatter graphs of 2 variables that influenced car prices:

Methodology used in the analysis

Methodology for car price influenced by age

The data collected in this study id through stratified sampling. The reason of using stratified sampling is that the price of the cars is reduced with the passage of time and to take the data in the strata form would be significant. The data of Toyota has been gathered as the brand and Yaris as the model. The stratified 25 samples were then collected. Other than 5 and 6 years, every year has been put 5 by samples. The research has been done on the highest and lowest prices of the cars and therefore the stratified samples would be extremely helpful because of continuous change in the prices as the car becomes old.

Methodology for car price influenced by mileage

The sampling used for analyzing the influence on cars through mileage is simple random sampling. The reason of using simple random sampling method is that this variable is much more independent. Initially, Mazda has been used as the brand, with any model on it. It used 25 samples with the lowest mileage is 148 miles and the highest mileage is 99000 miles.

Graph Evaluation

Regression Equation on both scatter graph of factor that influenced price of second hand car:

Car Price influenced by Age: y = -1307.3x + 11422

Car Price influenced by Mileage: y = -40.837x + 9258.4

Correlation calculation from the scatter graph:

Car price influenced by Age: R² = 0.7784

R = -0.882

Car price influenced by Mileage: R² = 0.4927

R = -0.702

The relationship of correlation and regression equation with the price of second hand car

Car price influenced by age

The correlation is strongly negative. It shows that the second hand car price is relatively depends onage. The ideal value of negative correlation coefficient is -1. However, the correlation coefficient in this case is -0.882. That mean the correlation is strong.The graph shows the correlation is strongly negative. It means that generally, the younger age of the car, the more expensive the price of second hand car will be.

Car price influenced by mileage

The negative correlation shows that the second handcar price depends onhow far the car has been used for the journey, in other words the mileage. The ideal value of negative correlation coefficient is -1. Therefore, the correlation coefficient in this case is -0.702. It means the correlation power is relatively strong. Obviously, mileage will affect the price of second hand car. Based on the scatter graph with the correlation calculations, it can be seen that the less miles means the price of the second hand car will be higher.

Conclusion

In conclusion, definitely, both variables are able to affect the price of second hand car. After conducted a sampling, made charts, and did calculations for both variables, it can be concluded that age is more able to influence the second hand car price based on the correlation calculation. Therefore, the factor of age is the best indicator to affect price of the ...