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Finding the Fourth Proportional to 254.20, 381.04 and 138.40

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Solution

The fourth proportional to 254.20, 381.04 and 138.40 is: 207.46

Step by Step Solution

  1. Step 1: Write the proportion equation
    254.20 : 381.04 = 138.40 : x
  2. Step 2: Convert to fraction form
    254.20/381.04 = 138.40/x
  3. Step 3: Cross multiply
    254.20x = 381.04 × 138.40
  4. Step 4: Simplify right side
    254.20x = 52,735.59
  5. Step 5: Solve for x
    x = 52,735.59/254.20
  6. Step 6: Final answer
    x = 207.46

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.