How does the lender in a payday loan make sure he or she doesnt lose money?

My math teacher told my class to "steal" a 6th grade fraction word problem from the internet, word problems? : -p requirements: only a 1 step word problem. needs to be complex.

The value, v, of kalani’s stock investments over a time period, x, can be determined using the equation v=750(0.80)^-x. what is the rate of increase or decrease associated with this account? 20% decrease 20% increase 25% decrease 25% increase

Which point does not lie on the graph k(x) = 8 -3 √x a. (-64, 12) b. (125, 3) c. (343, 1) d. (8, 5)