Answer:
a)
i) Interquartile range is  2.4 Â
ii) Upper boundary is 10.8 Â
The Lower boundary is 1.2 Â
iii) Outliers are points above the upper boundary or below the lower boundary Â
There is one outlier: 1.1
b) The modified boxplot with one outlier is given in the diagram. Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â
c) The 80th percentile is  Â
The minimum rating the hotel can get is 7.3
Step-by-step explanation:
a)
i) Interquartile range is Â
IQR = Q3-Q1 = 7.2-4.8 = 2.4 Â
ii) Upper boundary = Q3+ 1.5 *IQR = 7.2+1.5*2.4 = 10.8 Â
Lower boundary = Q1 - 1.5*IQR = 4.8- 1.5*2.4 = 1.2 Â
iii) Outliers are points above the upper boundary or below the lower boundary Â
There is one outlier: 1.1 Â
c) The 80th percentile is given by Â
n= 12 Â
k = 0.80 Â
Index is given by k*n =0.80*12 = 9.6 Â
Round to nearest whole number, that is 10th Â
80th percentile is the 10th number (arranged in ascending order) Â
80th percentile = 7.3 Â
The minimum rating the hotel can get is 7.3.
b) The modified boxplot with one outlier is given as follows, Â