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Finding the Fourth Proportional to 610.80, 915.77 and 285.99

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Solution

The fourth proportional to 610.80, 915.77 and 285.99 is: 428.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    610.80 : 915.77 = 285.99 : x
  2. Step 2: Convert to fraction form
    610.80/915.77 = 285.99/x
  3. Step 3: Cross multiply
    610.80x = 915.77 × 285.99
  4. Step 4: Simplify right side
    610.80x = 261,901.92
  5. Step 5: Solve for x
    x = 261,901.92/610.80
  6. Step 6: Final answer
    x = 428.78

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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.