Element X is a radioactive isotope such that every 11 years, its mass decreases by half. Given that the initial mass of a sample of Element X is 60 grams, how much of the element would remain after 25 years, to the nearest whole number?

Ending Amount = beginning amount / 2^n  where "n" is the number of half-lives or elapsed time / half-life

For this problem "n" = 25 / 11 = 2.2727272727

Ending Amount = 60 grams / 2^2.2727272

Ending Amount = 60 / 4.832357534

Ending Amount = 12.4162998242 grams

Source: www.1728.org/halflife.htm

Step-by-step explanation:

the formula of a slope:

from a table we have

substitute:

the slope of f(x) is -1.

the graph of funcfion g(x) is a horizontal line. the slope of a horizontal line is equal 0. therefore the slope of g(x) is 0.

-1 < 0