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Finding the Fourth Proportional to 609.91, 915.17 and 285.51

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Solution

The fourth proportional to 609.91, 915.17 and 285.51 is: 428.41

Step by Step Solution

  1. Step 1: Write the proportion equation
    609.91 : 915.17 = 285.51 : x
  2. Step 2: Convert to fraction form
    609.91/915.17 = 285.51/x
  3. Step 3: Cross multiply
    609.91x = 915.17 × 285.51
  4. Step 4: Simplify right side
    609.91x = 261,290.19
  5. Step 5: Solve for x
    x = 261,290.19/609.91
  6. Step 6: Final answer
    x = 428.41

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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.