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3 years ago

An element with a mass of 990 grams decays by 16.9% per minute. To the nearest

Mathematics

1 answer:

melamori03 [73]3 years ago

5 0

Answer:

It will take 13.58 minutes until there are 80 grams of the element remaining

Step-by-step explanation:

An element with a mass of 990 grams decays by 16.9% per minute.

We are supposed to find how long will it be until there are 80 grams of the element remaining

Formula : $N(t)=N_0(1-r)^t$

N(t)=Amount after t minutes

$N_0$ =Initial amount

r = rate of decrease = 0.169

t = time in minutes

Substitute the values in the formula :

$80=990(1-0.169)^t$

$\frac{80}{990}=0.831^t$

t=13.58

Hence It will take 13.58 minutes until there are 80 grams of the element remaining

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