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Finding the Fourth Proportional to 254.05, 380.76 and 138.40

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Solution

The fourth proportional to 254.05, 380.76 and 138.40 is: 207.43

Step by Step Solution

  1. Step 1: Write the proportion equation
    254.05 : 380.76 = 138.40 : x
  2. Step 2: Convert to fraction form
    254.05/380.76 = 138.40/x
  3. Step 3: Cross multiply
    254.05x = 380.76 × 138.40
  4. Step 4: Simplify right side
    254.05x = 52,697.18
  5. Step 5: Solve for x
    x = 52,697.18/254.05
  6. Step 6: Final answer
    x = 207.43

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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.