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Finding the Fourth Proportional to 645.04, 890.28 and 423.60

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Solution

The fourth proportional to 645.04, 890.28 and 423.60 is: 584.65

Step by Step Solution

  1. Step 1: Write the proportion equation
    645.04 : 890.28 = 423.60 : x
  2. Step 2: Convert to fraction form
    645.04/890.28 = 423.60/x
  3. Step 3: Cross multiply
    645.04x = 890.28 × 423.60
  4. Step 4: Simplify right side
    645.04x = 377,122.61
  5. Step 5: Solve for x
    x = 377,122.61/645.04
  6. Step 6: Final answer
    x = 584.65

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.