Please help.
A petri dish of bacteria grows continuously at a rate of 200% each day. If the petri dish began with 10 bacteria, how many bacteria are there after 5 days? Use the exponential growth function f(t) = aert, and give your answer to the nearest whole number.

The growth rate 200% gives r = 2. The initial number of bacteria is a = 10. Substitute these values into the growth function, then find the number of bacteria after 5 days by evaluating at t = 5.