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Finding the Fourth Proportional to 387.78, 580.76 and 306.08

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Solution

The fourth proportional to 387.78, 580.76 and 306.08 is: 458.39

Step by Step Solution

  1. Step 1: Write the proportion equation
    387.78 : 580.76 = 306.08 : x
  2. Step 2: Convert to fraction form
    387.78/580.76 = 306.08/x
  3. Step 3: Cross multiply
    387.78x = 580.76 × 306.08
  4. Step 4: Simplify right side
    387.78x = 177,754.59
  5. Step 5: Solve for x
    x = 177,754.59/387.78
  6. Step 6: Final answer
    x = 458.39

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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.