MATHEMATICS MIDDLE SCHOOL

Iodine-125 has a half-life of about 60 days.How many milligrams of a 500 mg sample will remain after 300 days?

1. 0.6 mg
2. 7.8125 mg
3. 15.625 mg
4. 31.25 mg

Answers

Answer 1
Answer: We know that Iodine - 125 has a half life of 60 days.
300 : 60 = 5 . It means that it was halved 6 times.
Therefore: 500 mg * 0.5^5 =
= 500 mg * 0.5 * 0.5 * 0.5 * 0.5 * 0.5 =
= 500 mg * 0.03125 = 15.625 mg
Answer: 3. 15.625 mg.
Answer 2
Answer:

Answer:

Step-by-step explanation:

15.625

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Answers

The company that offers the best deal in my point of view is Cellphones usually they are old so they are going in less price. I think that is what you mean

Answer:

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Step-by-step explanation:

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Answers

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Answers

Answer

Find out the how many minutes are spent preparing.

To proof

As given

A recipe takes 90 minutes to make.

25 percent of the time is spent preparing the ingredients.

25% is written in the decimal form

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Answers

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please help me and fast thanks

Answers

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Answers

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