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Finding the Fourth Proportional to 686.65, 1,029.95 and 199.69

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Solution

The fourth proportional to 686.65, 1,029.95 and 199.69 is: 299.52

Step by Step Solution

  1. Step 1: Write the proportion equation
    686.65 : 1,029.95 = 199.69 : x
  2. Step 2: Convert to fraction form
    686.65/1,029.95 = 199.69/x
  3. Step 3: Cross multiply
    686.65x = 1,029.95 × 199.69
  4. Step 4: Simplify right side
    686.65x = 205,664.57
  5. Step 5: Solve for x
    x = 205,664.57/686.65
  6. Step 6: Final answer
    x = 299.52

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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.