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Finding the Fourth Proportional to 512.70, 770.10 and 489.90

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Solution

The fourth proportional to 512.70, 770.10 and 489.90 is: 735.85

Step by Step Solution

  1. Step 1: Write the proportion equation
    512.70 : 770.10 = 489.90 : x
  2. Step 2: Convert to fraction form
    512.70/770.10 = 489.90/x
  3. Step 3: Cross multiply
    512.70x = 770.10 × 489.90
  4. Step 4: Simplify right side
    512.70x = 377,271.99
  5. Step 5: Solve for x
    x = 377,271.99/512.70
  6. Step 6: Final answer
    x = 735.85

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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.