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Finding the Fourth Proportional to 387.83, 581.55 and 127.78

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Solution

The fourth proportional to 387.83, 581.55 and 127.78 is: 191.61

Step by Step Solution

  1. Step 1: Write the proportion equation
    387.83 : 581.55 = 127.78 : x
  2. Step 2: Convert to fraction form
    387.83/581.55 = 127.78/x
  3. Step 3: Cross multiply
    387.83x = 581.55 × 127.78
  4. Step 4: Simplify right side
    387.83x = 74,310.46
  5. Step 5: Solve for x
    x = 74,310.46/387.83
  6. Step 6: Final answer
    x = 191.61

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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.