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Finding the Fourth Proportional to 497.70, 686.80 and 287.89

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Solution

The fourth proportional to 497.70, 686.80 and 287.89 is: 397.27

Step by Step Solution

  1. Step 1: Write the proportion equation
    497.70 : 686.80 = 287.89 : x
  2. Step 2: Convert to fraction form
    497.70/686.80 = 287.89/x
  3. Step 3: Cross multiply
    497.70x = 686.80 × 287.89
  4. Step 4: Simplify right side
    497.70x = 197,719.42
  5. Step 5: Solve for x
    x = 197,719.42/497.70
  6. Step 6: Final answer
    x = 397.27

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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.