OpenStax, Algebra and Trigonometry 2e §6.7 Exponential and Logarithmic Models · Exercise 37 · Algebra · Exponentials & logarithms

Exponential and Logarithmic Models · Exercise 37

Use this scenario: A tumor is injected with $0.5$ grams of Iodine-125, which has a decay rate of $1.15$ per day.

A scientist begins with $250$ grams of a radioactive substance. After $250$ minutes, the sample has decayed to $32$ grams. Rounding to five decimal places, write an exponential equation representing this situation. To the nearest minute, what is the half-life of this substance?

~8 minWritten answer · check your work with Lemma

OpenStax, Algebra and Trigonometry 2e · §6.7 Exponential and Logarithmic Models · Exercise 37

Stuck? A gentle nudge

No hints for this one.

Something off?

Workspace

Your working

Check your full solution

Attach photos of your pages (up to 3) or one PDF — or check what you typed above. Lemma reads the work and verifies the reasoning, not just the answer.

Your first check today doesn't need an account.

Your photos and PDFs are read once and not stored — only the transcription is kept.