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Finding the Fourth Proportional to 497.39, 686.31 and 287.57

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Solution

The fourth proportional to 497.39, 686.31 and 287.57 is: 396.79

Step by Step Solution

  1. Step 1: Write the proportion equation
    497.39 : 686.31 = 287.57 : x
  2. Step 2: Convert to fraction form
    497.39/686.31 = 287.57/x
  3. Step 3: Cross multiply
    497.39x = 686.31 × 287.57
  4. Step 4: Simplify right side
    497.39x = 197,358.74
  5. Step 5: Solve for x
    x = 197,358.74/497.39
  6. Step 6: Final answer
    x = 396.79

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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.