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After the release of radioactive material into the atmosphere from a nuclear power plant in a country in 1992​, the hay in that country was contaminated by a radioactive isotope​ (half-life 5 ​days). If it is safe to feed the hay to cows when 11​% of the radioactive isotope​ remains, how long did the farmers need to wait to use this​ hay?

User Karo
by
7.1k points

2 Answers

3 votes

Answer:

yes

Explanation:

1. 4

3x–1 = 8

x+1

2. 3

2x–1 = 20

3. log7

(5x + 3) = 3

4. log(3x + 1) – log 4 = 2

5. log4

(x – 1) + log4

(3x – 1) = 2

x ≈ 1.86

x = 68

x = 133

x = 3

x =

5

3

User Raz Harush
by
7.0k points
2 votes

Answer:

The farmer needs to wait at least 17 days or more for radioactive material to dissipate down to 11%.

Explanation:

Hope this helps. . . <3

User Matt Helliwell
by
7.3k points