Table 25 compares class standings with types of body art for 490 undergraduate students surveyed at a state university in the Southwest.

a. Find the proportion of those surveyed who have tattoos only.
b. Find the proportion of sophomores surveyed who have both body piercings and tattoos.
c. Find the proportion of juniors surveyed who have both body piercings and tattoos. Compare the result to your result in part (b).
d. A student says that the surveyed sophomores are more likely than the surveyed juniors to have both body piercing and tattoos because more sophomores (10) have both body piercing and tattoos than juniors (7). What would you tell the student?
e. On the basis of the two-way table, a student concludes that 11% of all college students in the United States have both body piercings and tattoos. What would you tell the student?

Table 25 Class Standing versus Types of Body Art Body Piercing Tattoos Piercing No Body Both Body Class Standing Only Only and Tattoos Art Total Freshman Sophomore Junior Senior Total 61 43 20 21 145 14 10 86 64 43 54 247 168 128 79 115 490 17 23 54