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Finding the Fourth Proportional to 628.65, 868.05 and 392.87

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Solution

The fourth proportional to 628.65, 868.05 and 392.87 is: 542.48

Step by Step Solution

  1. Step 1: Write the proportion equation
    628.65 : 868.05 = 392.87 : x
  2. Step 2: Convert to fraction form
    628.65/868.05 = 392.87/x
  3. Step 3: Cross multiply
    628.65x = 868.05 × 392.87
  4. Step 4: Simplify right side
    628.65x = 341,030.80
  5. Step 5: Solve for x
    x = 341,030.80/628.65
  6. Step 6: Final answer
    x = 542.48

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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.