12.1: Matching Situations and Equations
Match each equation to a situation it represents. Be prepared to explain how you know.
Note all equations have a match.
f(t) = 400 • (0.5)^0.1t
g(t) = 400 (1.25) ^0.1t
h(t) = 400 • (0.75)^0.1t
j(t) = 400 • (2)^10t
k(t) = 400 • (2)^0.1t
1. A scientist begins an experiment with 400 bacteria in a petri dish. The population
doubles every 10 hours. The function gives the number of bacteria t hours since the
experiment began.
2. A patient takes 400 mg of a medicine. The amount of medicine in her bloodstream
decreases by 25% every 10 hours. The function gives the amount of medicine left in
her bloodstream after t hours of taking the medicine.
smij
3. The half-life of a radioactive element is 10 years. There are 400 g of the element in a
sample when it is first studied. The function gives the amount of the element
remaining t years later.
4. In a lake, the population of a species of fish is 400. The population is expected to
grow by 25% in the next decade. The function gives the number of fish in the lake t
years after it was 400.