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Finding the Fourth Proportional to 101.40, 138.85 and 101.40

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Solution

The fourth proportional to 101.40, 138.85 and 101.40 is: 138.85

Step by Step Solution

  1. Step 1: Write the proportion equation
    101.40 : 138.85 = 101.40 : x
  2. Step 2: Convert to fraction form
    101.40/138.85 = 101.40/x
  3. Step 3: Cross multiply
    101.40x = 138.85 × 101.40
  4. Step 4: Simplify right side
    101.40x = 14,079.64
  5. Step 5: Solve for x
    x = 14,079.64/101.40
  6. Step 6: Final answer
    x = 138.85

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Why These Related Problems?

These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.