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Finding the Fourth Proportional to 497.91, 686.88 and 308.78

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Solution

The fourth proportional to 497.91, 686.88 and 308.78 is: 425.97

Step by Step Solution

  1. Step 1: Write the proportion equation
    497.91 : 686.88 = 308.78 : x
  2. Step 2: Convert to fraction form
    497.91/686.88 = 308.78/x
  3. Step 3: Cross multiply
    497.91x = 686.88 × 308.78
  4. Step 4: Simplify right side
    497.91x = 212,093.95
  5. Step 5: Solve for x
    x = 212,093.95/497.91
  6. Step 6: Final answer
    x = 425.97

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.