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Finding the Fourth Proportional to 686.91, 1,029.66 and 275.87

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Solution

The fourth proportional to 686.91, 1,029.66 and 275.87 is: 413.51

Step by Step Solution

  1. Step 1: Write the proportion equation
    686.91 : 1,029.66 = 275.87 : x
  2. Step 2: Convert to fraction form
    686.91/1,029.66 = 275.87/x
  3. Step 3: Cross multiply
    686.91x = 1,029.66 × 275.87
  4. Step 4: Simplify right side
    686.91x = 284,047.16
  5. Step 5: Solve for x
    x = 284,047.16/686.91
  6. Step 6: Final answer
    x = 413.51

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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.