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Finding the Fourth Proportional to 686.18, 1,028.58 and 377.72

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Solution

The fourth proportional to 686.18, 1,028.58 and 377.72 is: 566.20

Step by Step Solution

  1. Step 1: Write the proportion equation
    686.18 : 1,028.58 = 377.72 : x
  2. Step 2: Convert to fraction form
    686.18/1,028.58 = 377.72/x
  3. Step 3: Cross multiply
    686.18x = 1,028.58 × 377.72
  4. Step 4: Simplify right side
    686.18x = 388,511.62
  5. Step 5: Solve for x
    x = 388,511.62/686.18
  6. Step 6: Final answer
    x = 566.20

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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.