Final answer:
Jen can expect approximately 30 applications from the 13-oz bottle of self-tanning lotion.
Step-by-step explanation:
To determine how many applications of the self-tanning lotion Jen can expect from the 13-oz bottle, we can set up a proportion using the information given in the advertising claims. The proportion is:
3 oz / 7 applications = 13 oz / x applications
To solve for x, we can cross-multiply and solve for the unknown:
3x = 91
x = 91 / 3 = 30.33
Jen can expect approximately 30 applications from the 13-oz bottle of self-tanning lotion.