<span>In order to add and subtract fractions, we must be able to find a <u>common denominator</u>.
The LCD, or least common denominator, is the LCM of the denominators. Once we've added, subtracted or multiplied fractions, we often have to simplify the fraction.
In order to do this, we divide the numerator and denominator by their GCF. This means we must be able to find the LCM and GCF in order to work with fractions.</span>
Using the Empirical Rule, it is found that:
- a) Approximately 99.7% of the amounts are between $35.26 and $51.88.
- b) Approximately 95% of the amounts are between $38.03 and $49.11.
- c) Approximately 68% of the amounts fall between $40.73 and $46.27.
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The Empirical Rule states that, in a <em>bell-shaped </em>distribution:
- Approximately 68% of the measures are within 1 standard deviation of the mean.
- Approximately 95% of the measures are within 2 standard deviations of the mean.
- Approximately 99.7% of the measures are within 3 standard deviations of the mean.
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Item a:


Within <em>3 standard deviations of the mean</em>, thus, approximately 99.7%.
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Item b:


Within 2<em> standard deviations of the mean</em>, thus, approximately 95%.
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Item c:
- 68% is within 1 standard deviation of the mean, so:


Approximately 68% of the amounts fall between $40.73 and $46.27.
A similar problem is given at brainly.com/question/15967965
Answer:
6 dollars
Step-by-step explanation:
40-10=30
30/5= 6