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3 years ago

How much of a radioactive kind of xenon will be left after 15 days if the half-life is 5 days and

Mathematics

2 answers:

In-s [12.5K]3 years ago

7 0

Answer:

12 grams

Step-by-step explanation:

15/5 = 3 half lives

(1/2)³ = 1/8 of the original amount will remain

96 * 1/8 = 12 grams

Andrews [41]3 years ago

4 0

Answer:

Step-by-step explanation:

Radioactive decay problems are very similar to compound interest formulas, except the rate is subtracted from one, instead of adding to one.

I.e.

mass at time t, m(t) = M (1 - r)^(t/h)

where

M = initial mass (grams)

m (t) mass left at time t (grams)

h = half-life in number of days

r = 0.5 from "half-life"

t = time lapse in number of days

Here

M = 96

h = 5

t = 15

m(15) = 96(1-0.5)^(15/5)

= 96 (1/2)^3

= 12 grams

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kipiarov [429]

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Step-by-step explanation:

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