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Finding the Fourth Proportional to 409.80, 568.13 and 387.90

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Solution

The fourth proportional to 409.80, 568.13 and 387.90 is: 537.77

Step by Step Solution

  1. Step 1: Write the proportion equation
    409.80 : 568.13 = 387.90 : x
  2. Step 2: Convert to fraction form
    409.80/568.13 = 387.90/x
  3. Step 3: Cross multiply
    409.80x = 568.13 × 387.90
  4. Step 4: Simplify right side
    409.80x = 220,377.63
  5. Step 5: Solve for x
    x = 220,377.63/409.80
  6. Step 6: Final answer
    x = 537.77

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Why These Related Problems?

These problems maintain the same ratio (1.39) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.