The decay of 277 mg of an isotope is described by the function A (t) = 277e-0.019t, where t is time in years. Find the amount left after 64 years. Round your answer to the nearest mg.

The decay of 277 mg of an isotope is described by the function

A (t) = 277e-0.019t,

where t is time in years.

To find the amount left after 64 years,

We substitute t = 64 in the expression.

A (t=64) = 277e-0.019 (64)

or A (t=64) = 277 * e-1.216

= 277 * 0.29

= 82 mg