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Finding the Fourth Proportional to 402.62, 604.01 and 128.80

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Solution

The fourth proportional to 402.62, 604.01 and 128.80 is: 193.23

Step by Step Solution

  1. Step 1: Write the proportion equation
    402.62 : 604.01 = 128.80 : x
  2. Step 2: Convert to fraction form
    402.62/604.01 = 128.80/x
  3. Step 3: Cross multiply
    402.62x = 604.01 × 128.80
  4. Step 4: Simplify right side
    402.62x = 77,796.49
  5. Step 5: Solve for x
    x = 77,796.49/402.62
  6. Step 6: Final answer
    x = 193.23

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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.