the half - life of a particular radioactive substance is 1 year. if you started with 40 grams of this…

the half - life of a particular radioactive substance is 1 year. if you started with 40 grams of this substance, how much of it would remain after 3 years? remaining amount = 40(1 - ?) remaining amount = i(1 - r)^t enter the number that belongs in the green box.

the half - life of a particular radioactive substance is 1 year. if you started with 40 grams of this substance, how much of it would remain after 3 years? remaining amount = 40(1 - ?) remaining amount = i(1 - r)^t enter the number that belongs in the green box.

Answer

Answer:

$0.5$

Explanation:

Step1: Recall half - life concept

The amount of a radioactive substance decays by half in each half - life period. The decay formula for a radioactive substance is $A = I(1 - r)^t$, where $I$ is the initial amount, $r$ is the decay rate per time unit, and $t$ is the number of time units. In the case of half - life, if the half - life is 1 year, in each 1 - year period, the amount of the substance becomes half of what it was before. So the decay rate $r$ for a 1 - year period (one half - life) is $0.5$ because the substance loses 50% of its mass in each half - life.