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Finding the Fourth Proportional to 686.62, 1,030.15 and 199.70

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Solution

The fourth proportional to 686.62, 1,030.15 and 199.70 is: 299.61

Step by Step Solution

  1. Step 1: Write the proportion equation
    686.62 : 1,030.15 = 199.70 : x
  2. Step 2: Convert to fraction form
    686.62/1,030.15 = 199.70/x
  3. Step 3: Cross multiply
    686.62x = 1,030.15 × 199.70
  4. Step 4: Simplify right side
    686.62x = 205,720.96
  5. Step 5: Solve for x
    x = 205,720.96/686.62
  6. Step 6: Final answer
    x = 299.61

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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.