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Finding the Fourth Proportional to 686.37, 946.98 and 387.57

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Solution

The fourth proportional to 686.37, 946.98 and 387.57 is: 534.73

Step by Step Solution

  1. Step 1: Write the proportion equation
    686.37 : 946.98 = 387.57 : x
  2. Step 2: Convert to fraction form
    686.37/946.98 = 387.57/x
  3. Step 3: Cross multiply
    686.37x = 946.98 × 387.57
  4. Step 4: Simplify right side
    686.37x = 367,021.04
  5. Step 5: Solve for x
    x = 367,021.04/686.37
  6. Step 6: Final answer
    x = 534.73

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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.