Question

How much of a radioactive kind of niobium will be left after 105 days if you start with 3,920 grams and the half-life is 35 days?

Answer 1

Answer:

"490 grams" would be the correct solution.

Step-by-step explanation:

The given values are:

Half time,

T = 35 days

Total time,

t = 105 days

As we know,

⇒ $A=A_o(\frac{1}{2} )^{\frac{t}{T} }$

On substituting the values, we get

⇒     $=3920\times (\frac{1}{2})^{\frac{105}{35} }$

⇒     $=3920\times (0.5)^3$

⇒     $=3920\times 0.125$

⇒     $=490 \ grams$