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Finding the Fourth Proportional to 854.21, 1,279.24 and 487.89

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Solution

The fourth proportional to 854.21, 1,279.24 and 487.89 is: 730.65

Step by Step Solution

  1. Step 1: Write the proportion equation
    854.21 : 1,279.24 = 487.89 : x
  2. Step 2: Convert to fraction form
    854.21/1,279.24 = 487.89/x
  3. Step 3: Cross multiply
    854.21x = 1,279.24 × 487.89
  4. Step 4: Simplify right side
    854.21x = 624,124.53
  5. Step 5: Solve for x
    x = 624,124.53/854.21
  6. Step 6: Final answer
    x = 730.65

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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.