Finding Rational Numbers Between 1 and 2

Rational numbers are those that can be expressed as a fraction of two integers. Here's how we can find five rational numbers between 1 and 2.

Method 1: Using Averaging

1. Step 1: Average 1 and 2 to find the first rational number:

   • (1 + 2) / 2 = 3 / 2 = 1.5

2. Step 2: Repeat the process to find more rational numbers:

   • (1 + 1.5) / 2 = 2.5 / 2 = 1.25
   • (1.25 + 1.5) / 2 = 2.75 / 2 = 1.375
   • (1.25 + 1.375) / 2 = 2.625 / 2 = 1.3125
   • (1.3125 + 1.375) / 2 = 2.6875 / 2 = 1.34375

Method 2: Using Reciprocals

1. Step 1: Take the reciprocal of 2:

   • 1 / 2 = 0.5

2. Step 2: Repeat the process to find more rational numbers:

   • 1 / (2 + 1) = 1 / 3 ≈ 0.333
   • 1 / (3 + 1) = 1 / 4 = 0.25
   • 1 / (4 + 1) = 1 / 5 = 0.2
   • 1 / (5 + 1) = 1 / 6 ≈ 0.167

Summary:

• Rational numbers between 1 and 2: 1.5, 1.25, 1.375, 1.3125, 1.34375 (using averaging method)
• Rational numbers between 1 and 2: 0.5, 0.333, 0.25, 0.2, 0.167 (using reciprocal method)

These methods provide us with a variety of rational numbers between 1 and 2, demonstrating the flexibility and diversity of such numbers.

Locating √3 on the Number Line

Introduction Locating √3 on the number line is an essential concept in mathematics, particularly in understanding irrational numbers and their placement in relation to rational numbers.

Understanding √3 √3 represents the square root of 3, which is an irrational number. An irrational number cannot be expressed as a fraction of two integers and has an infinite non-repeating decimal expansion.

Steps to Locate √3 on the Number Line

1. Identify Nearby Perfect Squares:

   • √3 lies between the perfect squares of 1 and 4.
   • √1 = 1 and √4 = 2.

2. Estimation:

   • Since 3 is between 1 and 4, the square root of 3 will be between 1 and 2.
   • By estimation, √3 is approximately 1.732.

3. Plotting √3 on the Number Line:

   • Start at 0 on the number line.
   • Move to the right until you reach approximately 1.732 units.

4. Final Position:

   • Mark the point on the number line corresponding to √3.

Conclusion Locating √3 on the number line involves understanding its position between perfect squares and accurately plotting its approximate value. This skill is fundamental for comprehending the continuum of real numbers and their relationships.

Are the square roots of all positive integers irrational?

Introduction: The question probes into the nature of square roots of positive integers, whether they are exclusively irrational or if there are exceptions.

Explanation: The statement that the square roots of all positive integers are irrational is false. While there are indeed many examples of square roots that are irrational, there are also instances where the square root of a positive integer results in a rational number.

Example:

• Square root of 4:
  • Integer: 4
  • Square root: √4 = 2
  • Nature: Rational

Explanation of the Example:

• The square root of 4 is 2, which is a rational number.
• This contradicts the notion that all square roots of positive integers are irrational.

Conclusion: In conclusion, not all square roots of positive integers are irrational. The square root of 4, for instance, is a rational number, demonstrating that exceptions exist to the notion that all such roots are irrational.

Decimal Expansions of Fractions

1. Decimal Expansion of 10/3:

• Calculation:

  • Divide 10 by 3.
  • The result will be 3.3333...

• Decimal Expansion:

  • 103=3.3‾310=3.3

2. Decimal Expansion of 7/8:

• Calculation:

  • Divide 7 by 8.
  • The result will be 0.875.

• Decimal Expansion:

  • 78=0.87587=0.875

3. Decimal Expansion of 1/7:

• Calculation:

  • Divide 1 by 7.
  • The result will be 0.142857142857...

• Decimal Expansion:

  • 17=0.142857‾71=0.142857

Conclusion:

• The decimal expansions for the given fractions are:
  • 103=3.3‾310=3.3
  • 78=0.87587=0.875
  • 17=0.142857‾71=0.142857

Expressing 0.3333… as a Fraction:

Understanding the Repeating Decimal:

• When we write 0.3333…, the 3's continue indefinitely, indicating a repeating decimal.

Notation:

• Let x = 0.3333…

Multiplying by 10:

• If we multiply both sides of x by 10, we get 10x = 3.3333…

Subtracting Original Equation:

• Now, let's subtract the original equation (x) from the new equation (10x):
  • 10x - x = 3.3333... - 0.3333...
  • 9x = 3

Solving for x:

• Dividing both sides by 9, we find:
  • x = 3/9

Simplifying the Fraction:

• Both 3 and 9 can be divided by 3:
  • x = 1/3

Conclusion:

• Therefore, 0.3333… can be expressed as 1/3.