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3 years ago

Will give brainliest to right answer please help!! 15 points -A sample of a radioactive isotope had an initial mass of 370 mg

Mathematics

2 answers:

rewona [7]3 years ago

5 0

Answer: 28

Step-by-step explanation:

Alex777 [14]3 years ago

4 0

Answer:

78 mg

Step-by-step explanation:

370 mg - 110 mg = 260 mg (amount decayed in the 8 total years)

260 mg ÷ 8 years = 32.5 mg decayed per year

32.5 × 9 years (years between 2008 and 2017) = 292.5 mg

370 mg - 292.5 mg = 77.5 mg, rounded to 78 mg

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3 years ago

Read 2 more answers

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kifflom [539]

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Step-by-step explanation:

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2 years ago

a car decreased in value from $980 to $720 in one year what was the per cent of decrease to the nearest whole per cent ?

kolezko [41]

The decrease was 27%.

Step-by-step explanation:

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Percent decrease = $\frac{Decreased/ amount}{Old value}*100$

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Rounding off to near whole percent

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The decrease was 27%.

Keywords: Percentage, subtraction

Learn more about subtraction at:

#LearnwithBrainly

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2 years ago