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Finding the Fourth Proportional to 499.77, 692.82 and 489.71

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Solution

The fourth proportional to 499.77, 692.82 and 489.71 is: 678.88

Step by Step Solution

  1. Step 1: Write the proportion equation
    499.77 : 692.82 = 489.71 : x
  2. Step 2: Convert to fraction form
    499.77/692.82 = 489.71/x
  3. Step 3: Cross multiply
    499.77x = 692.82 × 489.71
  4. Step 4: Simplify right side
    499.77x = 339,282.61
  5. Step 5: Solve for x
    x = 339,282.61/499.77
  6. Step 6: Final answer
    x = 678.88

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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.