Question

an element with mass 430 grams decays by 27.4% per minute. How much of the element is remaining after 19 minutes, to the nearest 10th of a gram?​

Answer 1

Answer:

1.0 gram (rounded from .98)

Step-by-step explanation:

So, this is an exponential equation, which are of the form $a*b^x$ where a is the initial amount and b is the decay (or growth) rate.  a is easy, 430, b though you have to make sure it is in decimal form.  So for percent form (like you have) just move the decimal place to the left two times, so 27.4% becomes .274.

Now we have the equation $430*.274^x$ which shows the scenario listed.  just plug in 19 for x.  

Do keep in mind if they were different units, like t decayed for 19 hours, you would have to convert those too.  Let me know if you need more of an explanation.