About 92 days are taken for 90 % of the material to <em>decay</em>.
The mass of radioisotopes (
), measured in milligrams, decreases exponentially in time (
), measured in days. The model that represents such decrease is described below:
(1)
Where:
- Initial mass, in milligrams.
- Current mass, in milligrams.
- Time constant, in days.
In addition, the time constant is defined in terms of half-life (
), in days:
(2)
If we know that 
, 
and 
, then the time required for decaying is:
About 92 days are taken for 90 % of the material to <em>decay</em>.
We kindly invite to check this question on half-life: brainly.com/question/24710827
hint the circle is 40 inches and the square is 100 inches
Answer:
2. ) {25}^{2x} - 1 = {125}^{3x} + 4
=> {25}^{2x} = {125}^{3x} + 4 +1
=> {(5)^(2)}^{2x} = {(5)^(3)}^{3x} + {5}^{1}
=> {5}^{4x} = {5}^{9x} + {5}^{1}
=> 4x = 9x + 1
=> 4x - 9x = 1
=> - 5x = 1
=> x = 1/-5
T=95
solve for t by simplifying both sides of the equation then isolating the variable
-12x = -48
-12x/-12 = -48/-12
x = 4
hope this helps
