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Finding the Fourth Proportional to 421.32, 628.97 and 418.41

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Solution

The fourth proportional to 421.32, 628.97 and 418.41 is: 624.62

Step by Step Solution

  1. Step 1: Write the proportion equation
    421.32 : 628.97 = 418.41 : x
  2. Step 2: Convert to fraction form
    421.32/628.97 = 418.41/x
  3. Step 3: Cross multiply
    421.32x = 628.97 × 418.41
  4. Step 4: Simplify right side
    421.32x = 263,165.25
  5. Step 5: Solve for x
    x = 263,165.25/421.32
  6. Step 6: Final answer
    x = 624.62

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.