A radioactive substance is decaying (it is changing into another element) according to the formula y = Ae^(-0.2x)

A radioactive substance is decaying (it is changing into another element) according to the formula y = Ae-0.2x where y is the amount of material remaining after x years. If the initial amount A = 80 grams, find the half life (time it takes for half of it to decompose) of this substance.

A. 3.465 yrs C. 2.485 yrs
B. 4.025 yrs D. 1.95 yrs

Solution