Question

An element with mass 310 grams decays by 8.9% per minute. How much of

the element is remaining after 19 minutes, to the nearest 10th of a gram?

Answer 1

52.7 g

Explanation:

We are given;

• Initial mass of the element is 310 g
• Rate of decay 8.9% per minute
• Time for the decay 19 minutes

We are required to determine the amount of the element that will remain after 19 minutes.

We can use the formula;

New mass = Original mass × (1-r)^n

Where n is the time taken and r is the rate of decay.

Therefore;

Remaining mass = 310 g × (1-0.089)^19

= 52.748 g

= 52.7 g (to the nearest 10th)

Thus, the mass that will remain after 9 minutes will be 52.7 g