How do I figure out the exponential functions that pass through the pair of points (1, .3) and (3, .003)?

Find equations for exponential functions that pass through the given pair of points. (Round all coefficients to 4 decimal places if necessary.)


(1, 0.3) and (3, 0.003)How do I figure out the exponential functions that pass through the pair of points (1, .3) and (3, .003)?
How about f(x) = 3*10^(-x) ? Maybe more obvious if you write the points as (1, 3/10^1) and (3, 3/10^3).