The half-life of a certain radioactive element is 1,250 years. What percent of the atoms remain 7,500 years?

a
25%
b
1.5625%
c
50%
d
6.25%

1 answer

The percent of atoms that remain after a given time can be calculated using the formula:

Percent Remaining = (1/2)^(t/h) * 100

Where:
t = time passed in years
h = half-life of the element in years

In this case, t = 7,500 years and h = 1,250 years. Plugging these values into the formula:

Percent Remaining = (1/2)^(7,500/1,250) * 100
Percent Remaining = (1/2)^6 * 100
Percent Remaining = (1/64) * 100
Percent Remaining = 1.5625%

Therefore, the correct answer is option b) 1.5625%.