The hydrocarbon emissions at idling speed in parts of million (ppm) for automobiles of 1980 and 1990 model years are given for 20 randomly selected cars.

1980 models:
141 359 247 940 882 494 306 210 105 880 200 223 188 940 241 190 300 435 241 380.
1990 models:
140 160 20 20 223 60 20 95 360 70 220 400 217 58 235 380 200 175 85 65
a)Compute the sample means for the two years.
b)Compute the sample medians for the two years.
c)Find the interquartile range for the two years.
d)Find the sample standard deviation for the two years and comment on the result.

Solutions:
* 1980 model: Sample mean= 395.1
Sample median= 260.25
Interquartile Range= 835
Standard Deviation= 281.06

* 1990 model: Sample mean= 160.15
Sample median = 145
Interquartile range = 380
Standard deviation= 119.39

Can someone plz check out the answers whether they're correct or not.!