A radioactive element has half-life period of 30 days. How much of it will be left after 90 days?

A radioactive element has half-life period of 30 days. How much of it will be left after 90 days?
A. `13.5%`
B. `46.5%`
C. `87.5%`
D. `90.15%`

Monjur Alahi

5 views

2025-01-04 04:42

1 Answers

Salim Ahmed Kawsar

Correct Answer - C
`90 "days" rarr 3 "half lives"`, left `1/8` i.e., `12.5%`
Disintegrated `= 100-12.5 = 87.5%`

5 views Answered 2023-02-05 15:29

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