An element with Mass 630 grams decays by 18.8% per minute. How much of the element is remaining after 7 minutes, to the nearest 10th of a gram?

Question

asked Mar 4, 2019 160k views

1 Answer

Winker · Answer 1 · 2019-03-09T21:32:37+0000

Answer:

146.6 grams

Explanation:

We have been given an element with Mass 630 grams decays by 18.8% per minute.

We will use exponential decay function to solve our given problem.

$y=a\cdot (1-r)^x$ , where,

y = Final amount,

a = Initial amount,

r = Rate of decay in decimal form,

x = Time.

$18.8\%=(18.8)/(100)=0.188$

Substitute the given values:

$y=630\cdot (1-0.188)^7$

$y=630\cdot (0.812)^7$

$y=630\cdot 0.232751347$

y=146.633349

$y\approx 146.6$

Therefore, 146.6 grams of the element is remaining after 7 minutes.