Question

The developer of a new filter for filter-tipped cigarettes claims that it leaves less nicotine in the smoke than does the current filter. Because cigarette brands differ in a number of ways, he tests each filter on one cigarette of each of nine randomly selected brands and records the difference in nicotine content. His results are given in the table below.

Brand	A	B	C	D	E	F	G	H	J
Old Filter nicotine, mg	0.7	0.8	0.8	0.9	0.9	1.0	1.2	1.2	1.8
New Filter nicotine, mg	0.6	0.6	0.7	0.8	0.7	1.0	0.8	0.9	1.5

Does the data give convincing evidence that the filter tips leave less nicotine in the smoke? Follow the 4-step process.

old=c(.7, .8, .8, .9, .9, 1, 1.2, 1.2, 1.8)

new=c(.6, .6, .7, .8, .7, 1, .8, .9, 1.5)

Answer 1