Question

The "cold start ignition time" of an automobile engine is being investigated by a gasoline manufacturer. The following times (in seconds) were obtained for a test vehicle: 1.76, 1.84, 2.71, 2.26, 3.15, 3.21, 2.48, 1.87.

A second formulation of the gasoline was tested in the same vehicle, with the following times (in seconds): 1.75, 2.08, 3.17, 3.21, 2.74, 2.83, 3.47, 2.47, 1.98, and 3.39. Use this new data along with the cold start times to construct comparative box plots.

Construct the boxplot.

Answer 1

Let X= cold start ignition time

Y = formulation of the gasoline

Using R

> x<-c(1.76,1.84,2.71,2.26,3.15,3.21,2.48,1.87)
> y<-c(1.75,2.08,3.17,3.21,2.74,2.83,3.47,2.47,1.98,3.39)
> summary(x)
Min. 1st Qu. Median Mean 3rd Qu. Max.
1.760 1.863 2.370 2.410 2.820 3.210
> summary(y)
Min. 1st Qu. Median Mean 3rd Qu. Max.
1.750 2.178 2.785 2.709 3.200 3.470
> boxplot(x,y,main="Boxplot of cold start ignition time and formulation of the gasoline",ylab="time in seconds",names=c("cold start ignition time","formulation of the gasoline"))
>

The comparative box plots is given below