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Finding the Fourth Proportional to 428.52, 645.92 and 418.80

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Solution

The fourth proportional to 428.52, 645.92 and 418.80 is: 631.27

Step by Step Solution

  1. Step 1: Write the proportion equation
    428.52 : 645.92 = 418.80 : x
  2. Step 2: Convert to fraction form
    428.52/645.92 = 418.80/x
  3. Step 3: Cross multiply
    428.52x = 645.92 × 418.80
  4. Step 4: Simplify right side
    428.52x = 270,511.30
  5. Step 5: Solve for x
    x = 270,511.30/428.52
  6. Step 6: Final answer
    x = 631.27

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Why These Related Problems?

These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.