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Finding the Fourth Proportional to 609.70, 915.34 and 285.28

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Solution

The fourth proportional to 609.70, 915.34 and 285.28 is: 428.29

Step by Step Solution

  1. Step 1: Write the proportion equation
    609.70 : 915.34 = 285.28 : x
  2. Step 2: Convert to fraction form
    609.70/915.34 = 285.28/x
  3. Step 3: Cross multiply
    609.70x = 915.34 × 285.28
  4. Step 4: Simplify right side
    609.70x = 261,128.20
  5. Step 5: Solve for x
    x = 261,128.20/609.70
  6. Step 6: Final answer
    x = 428.29

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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.