List Five Rational Numbers Between -4/5 And -2/3 . Please Tell By Step By Step Explanation
Finding rational numbers between two given fractions is a common problem in mathematics that helps develop understanding of number lines, fractions, and rational numbers. This article provides a comprehensive, step-by-step guide to identify five rational numbers lying between \(-\frac{4}{5}\) and \(-\frac{2}{3}\). We will systematically explain the process, including converting fractions to comparable forms, finding common denominators, and selecting suitable rational numbers. Whether you're a student preparing for exams or someone interested in mathematical reasoning, this guide aims to clarify the method thoroughly.
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Understanding Rational Numbers and the Given Fractions
What Are Rational Numbers?
- Rational numbers are numbers that can be expressed as the quotient or fraction \(\frac{p}{q}\), where \(p\) and \(q\) are integers, and \(q \neq 0\).
- Examples include \(\frac{1}{2}\), \(-\frac{3}{4}\), 0, and integers like 5 (which can be written as \(\frac{5}{1}\)).
Given Fractions: \(-\frac{4}{5}\) and \(-\frac{2}{3}\)
- Both fractions are negative, indicating they lie to the left of zero on the number line.
- Our goal is to find five rational numbers between these two fractions.
Step 1: Convert Fractions to a Common Denominator
To compare fractions efficiently, especially when finding numbers lying between them, it's best to convert both to equivalent fractions with a common denominator.
Find the Least Common Denominator (LCD)
- Denominator of \(-\frac{4}{5}\): 5
- Denominator of \(-\frac{2}{3}\): 3
- LCD of 5 and 3: 15 (since 15 is the smallest number divisible by both 5 and 3)
Convert both fractions to have denominator 15
- \(-\frac{4}{5}\): multiply numerator and denominator by 3
- \(-\frac{2}{3}\): multiply numerator and denominator by 5
Now, the fractions are:
- \(-\frac{12}{15}\)
- \(-\frac{10}{15}\)
Since \(-\frac{12}{15}\) is less than \(-\frac{10}{15}\), the numbers lying between them are greater than \(-\frac{12}{15}\) and less than \(-\frac{10}{15}\).
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Step 2: Understand the Number Line and the Range
- The number line segment of interest is between \(-\frac{12}{15}\) and \(-\frac{10}{15}\).
- Recognize that these are negative numbers: \(-0.8\) and \(-0.666...\).
- Our task is to find rational numbers greater than \(-0.8\) and less than \(-0.666...\).
Step 3: Find Rational Numbers Between \(-\frac{12}{15}\) and \(-\frac{10}{15}\)
To find rational numbers between these two fractions, consider their decimal equivalents:
- \(-\frac{12}{15} = -0.8\)
- \(-\frac{10}{15} \approx -0.6667\)
Any rational number greater than \(-0.8\) and less than \(-0.6667\) will satisfy the condition.
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Step 4: Selecting Rational Numbers Between the Two Fractions
There are multiple methods to find rational numbers in between. Here, we will explore two common approaches:
Method 1: Find fractions with a common denominator between 15 and a higher denominator for more options
- Increase the denominator to find finer fractions.
- For example, choose denominator 30 (double 15):
- Convert \(-\frac{12}{15}\) to denominator 30:
- Convert \(-\frac{10}{15}\) to denominator 30:
- Now, the fractions are:
- \(-\frac{24}{30}\) (which is \(-0.8\))
- \(-\frac{20}{30}\) (which is \(-0.6667\))
- Rational numbers between these can then be selected as fractions with denominator 30, with numerators between 20 and 24:
- \(-\frac{23}{30}\)
- \(-\frac{22}{30}\)
- \(-\frac{21}{30}\)
- Simplify where possible:
- \(-\frac{23}{30}\) (cannot be simplified)
- \(-\frac{22}{30} = -\frac{11}{15}\) (since 2 and 30 are divisible by 2)
- \(-\frac{21}{30} = -\frac{7}{10}\)
- So, three rational numbers between the original fractions are:
- \(-\frac{23}{30}\)
- \(-\frac{11}{15}\)
- \(-\frac{7}{10}\)
Method 2: Use decimal approximations and convert back to fractions
- Pick decimal numbers between -0.8 and -0.6667, such as:
- \(-0.75\)
- \(-0.72\)
- \(-0.69\)
- \(-0.68\)
- \(-0.67\)
- Convert these to fractions:
- \(-0.75 = -\frac{3}{4}\)
- \(-0.72 = -\frac{18}{25}\)
- \(-0.69 = -\frac{69}{100}\)
- \(-0.68 = -\frac{17}{25}\)
- \(-0.67 \approx -\frac{67}{100}\)
- Check if these are between \(-\frac{12}{15}\) and \(-\frac{10}{15}\):
- \(-\frac{3}{4} = -0.75\) (less than \(-0.8\), so not between)
- \(-\frac{18}{25} = -0.72\) (between \(-0.8\) and \(-0.6667\))
- \(-\frac{69}{100} = -0.69\) (between)
- \(-\frac{17}{25} = -0.68\) (between)
- \(-\frac{67}{100} = -0.67\) (just slightly greater than \(-0.6667\), so perhaps just outside the range)
- From this, select five suitable rational numbers:
- \(-\frac{18}{25}\)
- \(-\frac{69}{100}\)
- \(-\frac{17}{25}\)
- \(-\frac{33}{50}\) (which is \(-0.66\))
- \(-\frac{13}{20}\) (which is \(-0.65\))
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Step 5: Final List of Five Rational Numbers Between the Given Fractions
Based on the methods above, here are five rational numbers that lie between \(-\frac{4}{5}\) and \(-\frac{2}{3}\):
- \(-\frac{23}{30}\) (approx. \(-0.7667\))
- \(-\frac{11}{15}\) (approx. \(-0.7333\))
- \(-\frac{7}{10}\) (exactly \(-0.7\))
- \(-\frac{18}{25}\) (approx. \(-0.72\))
- \(-\frac{69}{100}\) (approx. \(-0.69\))
All these fractions are greater than \(-0.8\) and less than \(-0.6667\), meaning they are strictly between \(-\frac{4}{5}\) and \(-\frac{2}{3}\).
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