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3 years ago

The half-life of radium is 1690 years. If 20 grams are present now, how much will be present in 250 years?

Mathematics

1 answer:

Aneli [31]3 years ago

3 0

Answer:

18.05 g

Step-by-step explanation:

The multiplier of the initial quantity is ...

(1/2)^(t/1690)

so, for t=250, this becomes ...

(1/2)^(250/1690) ≈ 0.902545

Then the quantity remaining of the initial 20 g is ...

(20 g)(0.902545) ≈ 18.05 g

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3 years ago

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3 years ago

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Oduvanchick [21]

Awnser

y=13

Step-by-step explanation:

-3x+2y=56

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so first we want to get rid of one variable, in this example we dont need to multiply because the y's cancel out

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3 years ago

Read 2 more answers

The​ half-life of radium is 1690 years. If 20 grams are present​ now, how much will be present in 250 ​years?

The half-life of radium is 1690 years. If 20 grams are present now, how much will be present in 250 years?